I have 2 devices, and I inadvertently set up a new account on one. Now I can't download books that are on my Nook to my Android G3 and vice versa. I can't remember the login for the nook. How can I change it?

I inadvertently set up a new account on an android and it doesn't match the ID for a Nook.  I cannot share library books between the devices, and I can't remember the login I used for the nook.  The nook books appear on my bookshelf from the library, but when I try to download to my android, it won't allow it as it is set up as a different account.  The library can't help me and Barnes & Noble can't help me.  I need support from Adobe to fix my login.