Error - Code E_AUTH_BAD_DEVICE_KEY On iPad Pro

I used to be able to download digital files from Netgalley.com but now I get  this error message. I tried to de-authorize my account but it spins and spins and nothing happens. If I remove and re-install the app, I will lose all my titles which are no longer available. I don’t understand why anyone uses your digital format instead of the kindle which always works. I am at the point of never selecting a book in the protected file format that takes me to ADE.