I’ve just tried following your exact steps and a photo from Google photos is saved OK against the payee.
I’m on Android 13, app v5.37.0 - but a Pixel 5 phone.
Try the reset-dance : uninstall the Monzo app, restart your device (important), download+install the Monzo app, login to the Monzo app - retry to see if the issue is resolved or not. This clears 99% of ‘strange’ issues.
If it remains, it may be linked to permissions or even a weird OS-related issue.
Hi both, thanks for the help. Tried the reset dance , didn’t seem to do anything. Also messed around with app settings, but no change. It is probably a MIUI/Xiaomi issue, I’ve had issues with other apps before that only seem to occur on Xiaomi phones and work fine on everything else.