iPad Books keeps downloading PDFs
Sorry, this is the second time I've posted this because a mis-click hit the "This solved my problem" button - which had NO confirmation dialog - when the problem was NOT in fact solved, and I can't "un-solve" it. Very frustrating.
The problem again...
Books on both my iPad Air and iPad Pro has periods where it will insist on downloading random PDF’s I have synced via iCloud. If I remove the download, it re-downloads again a few seconds later. Sometimes it will be one book, sometimes a dozen or more, all apparently randomly chosen from my collections. If I delete a PDF everywhere Books does stop downloading it, but as soon as I put the PDF back it downloads again. This will continue for hours, days or even weeks until I have my iPad cluttered with unwanted PDF’s, then it will suddenly stop for no reason and I can remove the downloads normally.
Restarting the iPad makes no difference, updating the iOS version makes no difference (currently on 15.1 but I've had the problem intermittently on previous versions). If I delete all my books from iCloud then add them back again it’s OK for a while then suddenly starts up again.
This is driving me insane, as well as taking up space on my iPad.
What can I do?
iPad Air 2, iPadOS 15