book covers not visible in android app

Hello, I have a lot of books: the website shows all covers: so it was in the android app on my Oneplus mobile phone. But since a a few weeks I see on my phone only the amazon-covers. I tried to re-install the app, but there is still the same problem. What can I do?

This is a known bug that the developers are presently researching.
Check for information on this thread:
https://www.librarything.com/topic/345680