Sony e-reader and authorization

I've had a Sony e-reader for many years. I opened my Adobe account years ago.  I recently purchased 3 e-books but can't read them on my reader. The message says the content is protected by DRM and asks do I want to input Adobe ID for authorization. When I do this it loops from input of ID etc back to Confirmation. I used the same ID and password to log on to this forum.

My reader is a PRS-T3S. The device information says that it is authorized for reading and purchasing Adobe DRM content.

Can anyone help me please.