System keeps asking for authorisation

I am trying to get my Reader for Mac to accept my authorisation password. It used to work and now I have  pile of books that I cannot read or access.  I have tried to deactivate and reimput but it still asks for authorisation. How do I open my books. Adobe has done this before and their shennaigans lost all my books and hundreds of pounds. Many of these books I cannot afford to replace so I need them opening!