diff --git a/contract-rs/01-basic-auction/src/lib.rs b/contract-rs/01-basic-auction/src/lib.rs
index 567e7df4..13f6cd75 100644
--- a/contract-rs/01-basic-auction/src/lib.rs
+++ b/contract-rs/01-basic-auction/src/lib.rs
@@ -1,6 +1,6 @@
 // Find all our documentation at https://docs.near.org
 use near_sdk::json_types::U64;
-use near_sdk::{env, near,require, AccountId, NearToken, PanicOnDefault, Promise};
+use near_sdk::{env, near, require, AccountId, NearToken, PanicOnDefault, Promise};
 
 #[near(serializers = [json, borsh])]
 #[derive(Clone)]
@@ -86,4 +86,4 @@ mod tests {
         let end_time = contract.get_auction_end_time();
         assert_eq!(end_time, U64::from(1000));
     }
-}
\ No newline at end of file
+}
diff --git a/contract-rs/01-basic-auction/tests/test_basics.rs b/contract-rs/01-basic-auction/tests/test_basics.rs
index f643ff17..8692a531 100644
--- a/contract-rs/01-basic-auction/tests/test_basics.rs
+++ b/contract-rs/01-basic-auction/tests/test_basics.rs
@@ -60,48 +60,38 @@ async fn test_contract_is_operational() -> Result<(), Box<dyn std::error::Error>
     let highest_bid_json = contract.view("get_highest_bid").await?;
     let highest_bid: Bid = highest_bid_json.json::<Bid>()?;
 
-    assert_eq!(
-        highest_bid.bid,
-        NearToken::from_near(1)
-    );
+    assert_eq!(highest_bid.bid, NearToken::from_near(1));
     assert_eq!(highest_bid.bidder, *alice.id());
 
-
     // Bob makes second bid
     let bob_bid = bob
-    .call(contract.id(), "bid")
-    .deposit(NearToken::from_near(2))
-    .transact()
-    .await?;
+        .call(contract.id(), "bid")
+        .deposit(NearToken::from_near(2))
+        .transact()
+        .await?;
 
     assert!(bob_bid.is_success());
 
     let highest_bid_json = contract.view("get_highest_bid").await?;
     let highest_bid: Bid = highest_bid_json.json::<Bid>()?;
 
-    assert_eq!(
-        highest_bid.bid,
-        NearToken::from_near(2)
-    );
+    assert_eq!(highest_bid.bid, NearToken::from_near(2));
     assert_eq!(highest_bid.bidder, *bob.id());
 
     // Alice makes the third bid but fails
     let alice_bid = alice
-    .call(contract.id(), "bid")
-    .deposit(NearToken::from_near(1))
-    .transact()
-    .await?;
+        .call(contract.id(), "bid")
+        .deposit(NearToken::from_near(1))
+        .transact()
+        .await?;
 
     assert!(alice_bid.is_failure());
 
     let highest_bid_json = contract.view("get_highest_bid").await?;
     let highest_bid: Bid = highest_bid_json.json::<Bid>()?;
 
-    assert_eq!(
-        highest_bid.bid,
-        NearToken::from_near(2)
-    );
+    assert_eq!(highest_bid.bid, NearToken::from_near(2));
     assert_eq!(highest_bid.bidder, *bob.id());
 
     Ok(())
-}
\ No newline at end of file
+}
diff --git a/contract-rs/02-owner-claims-money/src/lib.rs b/contract-rs/02-owner-claims-money/src/lib.rs
index 6ebda18c..839667db 100644
--- a/contract-rs/02-owner-claims-money/src/lib.rs
+++ b/contract-rs/02-owner-claims-money/src/lib.rs
@@ -15,7 +15,7 @@ pub struct Contract {
     highest_bid: Bid,
     auction_end_time: U64,
     auctioneer: AccountId,
-    auction_was_claimed: bool,
+    claimed: bool,
 }
 
 #[near]
@@ -26,10 +26,10 @@ impl Contract {
         Self {
             highest_bid: Bid {
                 bidder: env::current_account_id(),
-                bid: NearToken::from_yoctonear(0),
+                bid: NearToken::from_yoctonear(1),
             },
             auction_end_time: end_time,
-            auction_was_claimed: false,
+            claimed: false,
             auctioneer,
         }
     }
@@ -73,12 +73,11 @@ impl Contract {
     pub fn claim(&mut self) -> Promise {
         require!(
             env::block_timestamp() > self.auction_end_time.into(),
-            "Auction has ended"
+            "Auction has not ended yet"
         );
-        
-        require!(!self.auction_was_claimed, "Auction has been claimed");
-        self.auction_was_claimed = true;
-        let auctioneer = self.auctioneer.clone();
-        Promise::new(auctioneer).transfer(self.highest_bid.bid)
+
+        require!(!self.claimed, "Auction has already been claimed");
+        self.claimed = true;
+        Promise::new(self.auctioneer.clone()).transfer(self.highest_bid.bid)
     }
 }
diff --git a/contract-rs/02-owner-claims-money/tests/test_basics.rs b/contract-rs/02-owner-claims-money/tests/test_basics.rs
index 007e62d8..ec58cfd7 100644
--- a/contract-rs/02-owner-claims-money/tests/test_basics.rs
+++ b/contract-rs/02-owner-claims-money/tests/test_basics.rs
@@ -1,6 +1,6 @@
 use chrono::Utc;
 use contract_rs::Bid;
-use near_sdk::{log, NearToken, Gas};
+use near_sdk::{log, Gas, NearToken};
 use serde_json::json;
 
 const FIVE_NEAR: NearToken = NearToken::from_near(5);
@@ -27,11 +27,11 @@ async fn test_contract_is_operational() -> Result<(), Box<dyn std::error::Error>
         .unwrap();
 
     let auctioneer = root
-    .create_subaccount("auctioneer")
-    .initial_balance(FIVE_NEAR)
-    .transact()
-    .await?
-    .unwrap();
+        .create_subaccount("auctioneer")
+        .initial_balance(FIVE_NEAR)
+        .transact()
+        .await?
+        .unwrap();
 
     let contract_account = root
         .create_subaccount("contract")
@@ -67,56 +67,46 @@ async fn test_contract_is_operational() -> Result<(), Box<dyn std::error::Error>
     let highest_bid_json = contract.view("get_highest_bid").await?;
     let highest_bid: Bid = highest_bid_json.json::<Bid>()?;
 
-    assert_eq!(
-        highest_bid.bid,
-        NearToken::from_near(1)
-    );
+    assert_eq!(highest_bid.bid, NearToken::from_near(1));
     assert_eq!(highest_bid.bidder, *alice.id());
 
-
     // Bob makes second bid
     let bob_bid = bob
-    .call(contract.id(), "bid")
-    .deposit(NearToken::from_near(2))
-    .transact()
-    .await?;
+        .call(contract.id(), "bid")
+        .deposit(NearToken::from_near(2))
+        .transact()
+        .await?;
 
     assert!(bob_bid.is_success());
 
     let highest_bid_json = contract.view("get_highest_bid").await?;
     let highest_bid: Bid = highest_bid_json.json::<Bid>()?;
 
-    assert_eq!(
-        highest_bid.bid,
-        NearToken::from_near(2)
-    );
+    assert_eq!(highest_bid.bid, NearToken::from_near(2));
     assert_eq!(highest_bid.bidder, *bob.id());
 
     // Alice makes the third bid but fails
     let alice_bid = alice
-    .call(contract.id(), "bid")
-    .deposit(NearToken::from_near(1))
-    .transact()
-    .await?;
+        .call(contract.id(), "bid")
+        .deposit(NearToken::from_near(1))
+        .transact()
+        .await?;
 
     assert!(alice_bid.is_failure());
 
     let highest_bid_json = contract.view("get_highest_bid").await?;
     let highest_bid: Bid = highest_bid_json.json::<Bid>()?;
 
-    assert_eq!(
-        highest_bid.bid,
-        NearToken::from_near(2)
-    );
+    assert_eq!(highest_bid.bid, NearToken::from_near(2));
     assert_eq!(highest_bid.bidder, *bob.id());
 
     // Auctioneer claims auction but did not finish
     let auctioneer_claim = auctioneer
-    .call(contract_account.id(), "claim")
-    .args_json(json!({}))
-    .gas(Gas::from_tgas(300))
-    .transact()
-    .await?;
+        .call(contract_account.id(), "claim")
+        .args_json(json!({}))
+        .gas(Gas::from_tgas(300))
+        .transact()
+        .await?;
     assert!(auctioneer_claim.is_failure());
 
     // Fast forward
@@ -125,23 +115,25 @@ async fn test_contract_is_operational() -> Result<(), Box<dyn std::error::Error>
     sandbox.fast_forward(blocks_to_advance).await?;
 
     let auctioneer_claim = auctioneer
-    .call(contract_account.id(), "claim")
-    .args_json(json!({}))
-    .gas(Gas::from_tgas(300))
-    .transact()
-    .await?;
+        .call(contract_account.id(), "claim")
+        .args_json(json!({}))
+        .gas(Gas::from_tgas(300))
+        .transact()
+        .await?;
 
     assert!(auctioneer_claim.is_success());
 
+    // TODO: Assert the auctioneer got the money
+
     // Auctioneer claims auction back but fails
-    let auctioneer_claim =auctioneer
-    .call(contract_account.id(), "claim")
-    .args_json(json!({}))
-    .gas(Gas::from_tgas(300))
-    .transact()
-    .await?;
+    let auctioneer_claim = auctioneer
+        .call(contract_account.id(), "claim")
+        .args_json(json!({}))
+        .gas(Gas::from_tgas(300))
+        .transact()
+        .await?;
 
     assert!(auctioneer_claim.is_failure());
 
     Ok(())
-}
\ No newline at end of file
+}
diff --git a/contract-rs/03-owner-claims-winner-gets-nft/src/lib.rs b/contract-rs/03-owner-claims-winner-gets-nft/src/lib.rs
index 1d66750e..3437ef8a 100644
--- a/contract-rs/03-owner-claims-winner-gets-nft/src/lib.rs
+++ b/contract-rs/03-owner-claims-winner-gets-nft/src/lib.rs
@@ -1,6 +1,6 @@
 // Find all our documentation at https://docs.near.org
-use near_sdk::json_types::{U64};
-use near_sdk::{env, near, require, AccountId, Gas, NearToken, PanicOnDefault,Promise};
+use near_sdk::json_types::U64;
+use near_sdk::{env, near, require, AccountId, Gas, NearToken, PanicOnDefault, Promise};
 
 pub mod ext;
 pub use crate::ext::*;
@@ -20,7 +20,7 @@ pub struct Contract {
     highest_bid: Bid,
     auction_end_time: U64,
     auctioneer: AccountId,
-    auction_was_claimed: bool,
+    claimed: bool,
     nft_contract: AccountId,
     token_id: TokenId,
 }
@@ -38,11 +38,11 @@ impl Contract {
         Self {
             highest_bid: Bid {
                 bidder: env::current_account_id(),
-                bid: NearToken::from_yoctonear(0),
+                bid: NearToken::from_yoctonear(1),
             },
             auction_end_time: end_time,
             auctioneer,
-            auction_was_claimed: false,
+            claimed: false,
             nft_contract,
             token_id,
         }
@@ -86,12 +86,11 @@ impl Contract {
             "Auction has not ended yet"
         );
 
-        assert!(!self.auction_was_claimed, "Auction has been claimed");
+        assert!(!self.claimed, "Auction has already been claimed");
 
-        self.auction_was_claimed = true;
-        let auctioneer = self.auctioneer.clone();
+        self.claimed = true;
 
-        Promise::new(auctioneer).transfer(self.highest_bid.bid);
+        Promise::new(self.auctioneer.clone()).transfer(self.highest_bid.bid);
 
         nft_contract::ext(self.nft_contract.clone())
             .with_static_gas(Gas::from_tgas(30))
diff --git a/contract-rs/03-owner-claims-winner-gets-nft/tests/test_basics.rs b/contract-rs/03-owner-claims-winner-gets-nft/tests/test_basics.rs
index 8c8b2ab6..3b7642a4 100644
--- a/contract-rs/03-owner-claims-winner-gets-nft/tests/test_basics.rs
+++ b/contract-rs/03-owner-claims-winner-gets-nft/tests/test_basics.rs
@@ -45,11 +45,11 @@ async fn test_contract_is_operational() -> Result<(), Box<dyn std::error::Error>
         .unwrap();
 
     let auctioneer = root
-    .create_subaccount("auctioneer")
-    .initial_balance(FIVE_NEAR)
-    .transact()
-    .await?
-    .unwrap();
+        .create_subaccount("auctioneer")
+        .initial_balance(FIVE_NEAR)
+        .transact()
+        .await?
+        .unwrap();
 
     let contract_account = root
         .create_subaccount("contract")
@@ -96,10 +96,10 @@ async fn test_contract_is_operational() -> Result<(), Box<dyn std::error::Error>
 
     // Alice makes first bid
     let alice_bid = alice
-    .call(contract.id(), "bid")
-    .deposit(NearToken::from_near(1))
-    .transact()
-    .await?;
+        .call(contract.id(), "bid")
+        .deposit(NearToken::from_near(1))
+        .transact()
+        .await?;
 
     assert!(alice_bid.is_success());
 
@@ -115,10 +115,10 @@ async fn test_contract_is_operational() -> Result<(), Box<dyn std::error::Error>
 
     // Bob makes second bid
     let bob_bid = bob
-    .call(contract.id(), "bid")
-    .deposit(NearToken::from_near(2))
-    .transact()
-    .await?;
+        .call(contract.id(), "bid")
+        .deposit(NearToken::from_near(2))
+        .transact()
+        .await?;
 
     assert!(bob_bid.is_success());
 
@@ -133,10 +133,10 @@ async fn test_contract_is_operational() -> Result<(), Box<dyn std::error::Error>
 
     // Alice makes the third bid but fails
     let alice_bid = alice
-    .call(contract.id(), "bid")
-    .deposit(NearToken::from_near(1))
-    .transact()
-    .await?;
+        .call(contract.id(), "bid")
+        .deposit(NearToken::from_near(1))
+        .transact()
+        .await?;
 
     assert!(alice_bid.is_failure());
 
@@ -151,11 +151,11 @@ async fn test_contract_is_operational() -> Result<(), Box<dyn std::error::Error>
 
     // Auctioneer claims auction but did not finish
     let auctioneer_claim = auctioneer
-    .call(contract_account.id(), "claim")
-    .args_json(json!({}))
-    .gas(Gas::from_tgas(300))
-    .transact()
-    .await?;
+        .call(contract_account.id(), "claim")
+        .args_json(json!({}))
+        .gas(Gas::from_tgas(300))
+        .transact()
+        .await?;
     assert!(auctioneer_claim.is_failure());
 
     // Fast forward
@@ -164,21 +164,25 @@ async fn test_contract_is_operational() -> Result<(), Box<dyn std::error::Error>
     sandbox.fast_forward(blocks_to_advance).await?;
 
     let auctioneer_claim = auctioneer
-    .call(contract_account.id(), "claim")
-    .args_json(json!({}))
-    .gas(Gas::from_tgas(300))
-    .transact()
-    .await?;
+        .call(contract_account.id(), "claim")
+        .args_json(json!({}))
+        .gas(Gas::from_tgas(300))
+        .transact()
+        .await?;
 
     assert!(auctioneer_claim.is_success());
 
+    // TODO:
+    // Auctioneer has the balance
+    // NFT is transferred to the highest bidder
+    
     // Auctioneer claims auction back but fails
-    let auctioneer_claim =auctioneer
-    .call(contract_account.id(), "claim")
-    .args_json(json!({}))
-    .gas(Gas::from_tgas(300))
-    .transact()
-    .await?;
+    let auctioneer_claim = auctioneer
+        .call(contract_account.id(), "claim")
+        .args_json(json!({}))
+        .gas(Gas::from_tgas(300))
+        .transact()
+        .await?;
 
     assert!(auctioneer_claim.is_failure());
 
diff --git a/contract-rs/04-ft-owner-claims-winner-gets-nft/src/lib.rs b/contract-rs/04-ft-owner-claims-winner-gets-nft/src/lib.rs
index 1d385126..8b487cee 100644
--- a/contract-rs/04-ft-owner-claims-winner-gets-nft/src/lib.rs
+++ b/contract-rs/04-ft-owner-claims-winner-gets-nft/src/lib.rs
@@ -20,7 +20,7 @@ pub struct Contract {
     highest_bid: Bid,
     auction_end_time: U64,
     auctioneer: AccountId,
-    auction_was_claimed: bool,
+    claimed: bool,
     ft_contract: AccountId,
     nft_contract: AccountId,
     token_id: TokenId,
@@ -44,7 +44,7 @@ impl Contract {
             },
             auction_end_time: end_time,
             auctioneer,
-            auction_was_claimed: false,
+            claimed: false,
             ft_contract,
             nft_contract,
             token_id,
@@ -61,15 +61,14 @@ impl Contract {
             "Auction has not ended yet"
         );
 
-        assert!(!self.auction_was_claimed, "Auction has been claimed");
+        assert!(!self.claimed, "Auction has been claimed");
 
-        self.auction_was_claimed = true;
-        let auctioneer = self.auctioneer.clone();
+        self.claimed = true;
 
         ft_contract::ext(self.ft_contract.clone())
             .with_attached_deposit(NearToken::from_yoctonear(1))
             .with_static_gas(Gas::from_tgas(30))
-            .ft_transfer(auctioneer, self.highest_bid.bid);
+            .ft_transfer(self.auctioneer.clone(), self.highest_bid.bid);
 
         nft_contract::ext(self.nft_contract.clone())
             .with_static_gas(Gas::from_tgas(30))
@@ -77,6 +76,7 @@ impl Contract {
             .nft_transfer(self.highest_bid.bidder.clone(), self.token_id.clone());
     }
 
+    // Users bid by transferring FT tokens
     pub fn ft_on_transfer(&mut self, sender_id: AccountId, amount: U128, msg: String) -> U128 {
         require!(
             env::block_timestamp() < self.auction_end_time.into(),
diff --git a/contract-ts/01-basic-auction/src/contract.ts b/contract-ts/01-basic-auction/src/contract.ts
index 03a5792c..484fa957 100644
--- a/contract-ts/01-basic-auction/src/contract.ts
+++ b/contract-ts/01-basic-auction/src/contract.ts
@@ -11,12 +11,10 @@ class AuctionContract {
   highest_bid: Bid = { bidder: '', bid: BigInt(0) };
   auction_end_time: bigint = BigInt(0);
 
-
   @initialize({ privateFunction: true })
   init({ end_time}: { end_time: bigint}) {
     this.auction_end_time = end_time;
-    this.highest_bid = { bidder: near.currentAccountId(), bid: BigInt(0) };
-
+    this.highest_bid = { bidder: near.currentAccountId(), bid: BigInt(1) };
   }
 
   @call({ payableFunction: true })
@@ -35,7 +33,7 @@ class AuctionContract {
     assert(bid > lastBid, "You must place a higher bid");
 
     // Update the highest bid
-    this.highest_bid = { bidder, bid }; // Save the new bid
+    this.highest_bid = { bidder, bid };
 
     // Transfer tokens back to the last bidder
     return NearPromise.new(lastBidder).transfer(lastBid);
diff --git a/contract-ts/02-owner-claims-money/src/contract.ts b/contract-ts/02-owner-claims-money/src/contract.ts
index 93a9f04f..17fb7314 100644
--- a/contract-ts/02-owner-claims-money/src/contract.ts
+++ b/contract-ts/02-owner-claims-money/src/contract.ts
@@ -6,20 +6,17 @@ class Bid {
   bid: bigint;
 }
 
-const THIRTY_TGAS = BigInt("20000000000000");
-const NO_DEPOSIT = BigInt(0);
-
 @NearBindgen({ requireInit: true })
 class AuctionContract {
   highest_bid: Bid = { bidder: '', bid: BigInt(0) };
   auction_end_time: bigint = BigInt(0);
   auctioneer: string = "";
-  auction_was_claimed: boolean = false;
+  claimed: boolean = false;
 
   @initialize({ privateFunction: true })
   init({ end_time, auctioneer}: { end_time: bigint, auctioneer: string}) {
     this.auction_end_time = end_time;
-    this.highest_bid = { bidder: near.currentAccountId(), bid: BigInt(0) };
+    this.highest_bid = { bidder: near.currentAccountId(), bid: BigInt(1) };
     this.auctioneer = auctioneer;
   }
 
@@ -57,15 +54,9 @@ class AuctionContract {
 
   @call({})
   claim() {
-   
     assert(this.auction_end_time <= near.blockTimestamp(), "Auction has not ended yet");
-    assert(!this.auction_was_claimed, "Auction has been claimed");
-
-    this.auction_was_claimed = true;
-
-    
+    assert(!this.claimed, "Auction has been claimed");
+    this.claimed = true;
     return NearPromise.new(this.auctioneer).transfer(this.highest_bid.bid)
-
   }
-
 }
\ No newline at end of file
diff --git a/contract-ts/03-owner-claims-winner-gets-nft/src/contract.ts b/contract-ts/03-owner-claims-winner-gets-nft/src/contract.ts
index 8ec07fc6..6be4f2b1 100644
--- a/contract-ts/03-owner-claims-winner-gets-nft/src/contract.ts
+++ b/contract-ts/03-owner-claims-winner-gets-nft/src/contract.ts
@@ -6,7 +6,7 @@ class Bid {
   bid: bigint;
 }
 
-const THIRTY_TGAS = BigInt("20000000000000");
+const TWENTY_TGAS = BigInt("20000000000000");
 const NO_DEPOSIT = BigInt(0);
 
 @NearBindgen({ requireInit: true })
@@ -14,14 +14,14 @@ class AuctionContract {
   highest_bid: Bid = { bidder: '', bid: BigInt(0) };
   auction_end_time: bigint = BigInt(0);
   auctioneer: string = "";
-  auction_was_claimed: boolean = false;
+  claimed: boolean = false;
   nft_contract: AccountId = "";
   token_id: string = "";
 
   @initialize({ privateFunction: true })
   init({ end_time, auctioneer, nft_contract, token_id }: { end_time: bigint, auctioneer: string, nft_contract: AccountId, token_id: string }) {
     this.auction_end_time = end_time;
-    this.highest_bid = { bidder: near.currentAccountId(), bid: BigInt(0) };
+    this.highest_bid = { bidder: near.currentAccountId(), bid: BigInt(1) };
     this.auctioneer = auctioneer;
     this.nft_contract = nft_contract;
     this.token_id = token_id;
@@ -61,26 +61,20 @@ class AuctionContract {
 
   @call({})
   claim() {
-   
     assert(this.auction_end_time <= near.blockTimestamp(), "Auction has not ended yet");
-    assert(!this.auction_was_claimed, "Auction has been claimed");
+    assert(!this.claimed, "Auction has been claimed");
+    this.claimed = true;
 
-    this.auction_was_claimed = true;
-
-    
     return NearPromise.new(this.nft_contract)
-      .functionCall("nft_transfer", JSON.stringify({ receiver_id: this.highest_bid.bidder, token_id: this.token_id }), BigInt(1), THIRTY_TGAS)
-      .and(NearPromise.new(this.auctioneer).transfer(this.highest_bid.bid))
-      .then(
-        NearPromise.new(near.currentAccountId())
-          .functionCall("nft_transfer_callback", JSON.stringify({}), NO_DEPOSIT, THIRTY_TGAS)
+      .functionCall(
+        "nft_transfer",
+        JSON.stringify({ receiver_id: this.highest_bid.bidder, token_id: this.token_id }),
+        BigInt(1),
+        TWENTY_TGAS
+      )
+      .and(
+        NearPromise.new(this.auctioneer).transfer(this.highest_bid.bid)
       )
       .asReturn()
-
   }
-
-  @call({ privateFunction: true })
-  nft_transfer_callback({ }): BigInt {
-    return BigInt(0);
-  }
-}
\ No newline at end of file
+}
diff --git a/contract-ts/04-ft-owner-claims-winner-gets-nft/src/contract.ts b/contract-ts/04-ft-owner-claims-winner-gets-nft/src/contract.ts
index de6b7958..2a4af592 100644
--- a/contract-ts/04-ft-owner-claims-winner-gets-nft/src/contract.ts
+++ b/contract-ts/04-ft-owner-claims-winner-gets-nft/src/contract.ts
@@ -14,7 +14,7 @@ class AuctionContract {
   highest_bid: Bid = { bidder: '', bid: BigInt(1) };
   auction_end_time: bigint = BigInt(0);
   auctioneer: string = "";
-  auction_was_claimed: boolean = false;
+  claimed: boolean = false;
   ft_contract: AccountId = "";
   nft_contract: AccountId = "";
   token_id: string = "";
@@ -41,25 +41,17 @@ class AuctionContract {
 
   @call({})
   claim() {
-   
     assert(this.auction_end_time <= near.blockTimestamp(), "Auction has not ended yet");
-    assert(!this.auction_was_claimed, "Auction has been claimed");
+    assert(!this.claimed, "Auction has been claimed");
 
-    this.auction_was_claimed = true;
+    this.claimed = true;
 
     return NearPromise.new(this.nft_contract)
       .functionCall("nft_transfer", JSON.stringify({ receiver_id: this.highest_bid.bidder, token_id: this.token_id }), BigInt(1), THIRTY_TGAS)
-      .and(NearPromise.new(this.ft_contract)
+      .and(
+        NearPromise.new(this.ft_contract)
         .functionCall("ft_transfer", JSON.stringify({ receiver_id: this.auctioneer, amount: this.highest_bid.bid }), BigInt(1), THIRTY_TGAS)
-        .then(
-          NearPromise.new(near.currentAccountId())
-            .functionCall("ft_transfer_callback", JSON.stringify({}), NO_DEPOSIT, THIRTY_TGAS)
-        ))
-      .then(
-        NearPromise.new(near.currentAccountId())
-          .functionCall("nft_transfer_callback", JSON.stringify({}), NO_DEPOSIT, THIRTY_TGAS)
-      )
-      .asReturn()
+      ).asReturn()
   }
 
   @call({})
@@ -95,9 +87,4 @@ class AuctionContract {
   ft_transfer_callback({ }): BigInt {
     return BigInt(0);
   }
-
-  @call({ privateFunction: true })
-  nft_transfer_callback({ }): BigInt {
-    return BigInt(0);
-  }
 }
\ No newline at end of file