I can´t read books anymore on my iPad

I try to borrow e-books on my iPad but get error messages, even though I have logged in to my Adobe. What is the problem? I have also deautorized my old Adobe on my old iPad. And authorized on my new. But i just get: Error: Cant find user identity due the bad device key or PKCS12. And: Error: Fullfillment is not complete. The book don´t even appear in DE. I have a new iPad.