In-app purchases are notoriously buggy on Android, especially when you have more than 1 account on your smartphone. The problem is that in-app purchases are always tied to a specific account, and if the app to which the in-app belongs is installed under a different account on your phone, it won’t be recognized. We consider it a bug, even though it is a logical one, not technical.
This is a companion discussion topic for the original entry at https://sleep.urbandroid.org/docs/general/start.html