Hi guys,
There are many threads for this issue already. Would be best to use one of those so it’s easier to track.
Here’s mine:
And here’s more users reporting the issue for u @Carlo1460 
The interim fix is to delete the app, restart your device, then reinstall the app. It’s not 100% reliable though, and may take a few attempts.
The most recent update from Monzo on this bug are here from a few months ago: