How do you Authorize in ADE when you don't know the 1) ebook vendor 2)Adobe ID and the Password?

How do you Authorize in ADE when you don't know the 1) ebook vendor 2)Adobe ID and the Password?

I have been trying to get one book downloaded onto the Adobe Digital Edition.  I could read them on my

computer.  However, there was one book that I could not read so KOBO told me to deauthorize the computer

and then reauthorize.  However, to reauthorize, you need to be able to answer 1,2 and 3 above.

I use what I consider my Id and password but they say they don't match.

  I have been at this with Adobe, Geek squad and KOBO for about eight hours and

getting very frustrated. 

Can anyone help?