[Sukeroku]

The issue had gone away, but now it's happening again. However, I know which book is causing the error this time, it definitely looks like a database issue as tshering said.

There is a book with messed up data which I can not delete no matter what.

Is there a more focused way to fix the error without having to reset everything AGAIN?

Also can I at least backup manually some of the data (that is not causing any issues)? Mostly reading progress.

EDIT: this is weird. Upon re-adding the books, even after resigning myself to refresh the database AGAIN, these two books still display incorrect data (like entire filename instead of the actual title, and "author unknown", despite these metadata being present in Calibre)