I'm one of the app testers (I can't remember if there's still two apps on the go...!!), and since the last update every time I open the app it asks me to sign in, pick a colour preference etc.
I'm using the app on my phone - iPhone 7 plus.
I know deleting and reinstalling the app is usually the first step, but I couldn't see where to reinstall the test app from (Test Flight is empty and asking for invitation codes?).
Thank you!