Error messages when downloading books from the library to my Nook

I have a Nook Simple Touch and use Adobe Digital Editions to transfer library books to my Nook. Recently I started getting a message that says "This book as been returned. Loan not on record." whenever I try to open in in my Nook. However, the book hasn't been returned. I can still open it in Adobe Digital Editions, as well as my library app on my phone. This happened before and restarting my Nook a couple times let me eventually open the books, but it's happening again and I can't fix it.