So a few months ago I left facebook and I kept using spotify normaly on my devices since I never logged off. I tried logging in a new device and couldn't do it, and I realized I had another account already registered on my email address. Anyway, is there a way to link a facebook-registered account to an email? And if so I believe I have to delete or deactivate this never used account I have on my mail, right? thanks a lot!
Try logging onto your Facebook and disconnecting your Spotify from Facebook. If you did register your current Spotify account through Facebook, you'll have to probably make another Spotify account with a new email.