Thanks for further details, I might have figured out something.
Could you tell me if you have Settings > Push notifications enabled?
Discussion
Seeing the same issue quite often. Notifications are enabled.
I've found potential cause. In case that a payment processed over NWC fails for whatever reason, I did not stop the android service for long lasting tasks.
This leads to Application not responding state.
Will release a fix 0.1.10-beta.8 now, let's see if it helps.
I do