Players do not receive shovels?

[ToxicTheFur]

When starting a game, after the countdown players will not receive shovels. At the most, the shovels will flash in the player's hot bar, but will immediately disappear. So far, only I, the server owner, have been able to receive a shovel. Please help.

[ToxicTheFur]

EDIT: Some players get a shovel before the countdown, but lose it after the countdown ends.