iOS app not able to connect to server, error code NSURLErrorDomain 1004

[rainbowhippy]

iOS device model, version and app version
iPhone 12 Pro running iOS 18.3

I can log in to Home Assistant in Chrome on my laptop (via homeassistant.local:8123 ) without any problem. It is definitely running ok as all my automations etc are working. However when I try and open the iPhone app, I get the following error -

I have deleted the app from my phone and reinstalled it but this has not yielded any different outcome.

[bgoncal]

Try using the IP instead of homeassistant.local

[rainbowhippy]

I'm not sure I understand, sorry. How do I do that in the iOS app? As soon as I open the iOS app, it shows the aforementioned error.

[bgoncal]

You can tap out of the warning message or wait until it dismisses then tap the gear icon, companion app settings will open, tap your server name, tap internal URL and replace by the IP