Can't get back to my original account.

I had over 4000 books in my collection and it randomly asked me to sign in. I accidentally signed in with a different email and now I can't sign out of the new account and get my old one back. The email account I'm sending this from is the one I need to get back. Please advise. Imported from our previous feedback board. Originally posted 2026-02-22 with 3 votes.