Why has my eReader stopped recognizing any books that I have downloaded.

Hello,

I have a KOBO Glo, which I have had for about 7 years.  I often borrow books from my local library, and up until one wek ago, I did not have any troubles.

When I bought the eReader, I downloaded Digial Editions, and made sure to authorize both the software (ADE) and the eReader itself.

It was working great up until one week ago.

I tried to get a book from the library and I received the "eReader is not authorized to read this book" message.  This is odd because I downloaded two books last week, and one of them worked fine (fine as in I could read it on the eReader), and the other got this message.

My ADE and eReader are both authorized, and the AdobeID Number is the same on both.

Now any books that I try to put on the eReader also gives me that "eReader is not authorized" message.

I do not know how all of a sudden the eReader can ust stop and not recognize any books now.

I do not know if there are any changes that have happened with online Library Book rentals or with ADE itself?

My KOBO GLO Model# N613

Any help on this would be appreciated.