Something happened recently - new books not opening

I love this app and buy a lot of books on parenting that I refer back to on a daily basis. I find the selection much better than on iTunes and prices often better than on Amazon Kindle. But recently I discovered that new books I purchased do not open - the app freezes up, books keep re-downloading and giving me error messages. Very frustrating.

Lidia Gribanova about Google Play Books - Books & Comics, v3.1.1