I can only read e-books on my laptop. How do I get them unto my e-reader? It has something to do with the Adobe ID.

Hello,

just now I downloaden an e-book from the library and I wanted to copy it to my e-reader. I needed an Adobe ID but I forgot my password (and the website to get a new password wasn't working) so I clicked on 'open without authorization' but now I can only read the book on my laptop and not copy it unto my e-reader. Anyone an idea how I can  undo this? Because I did manage to retrieve a new password.

Thanks for your help!