Hi there! Did you create your account with Facebook? If so, you'll need to create a new Spotify account if you want it to be created with an email and a username, or with a new Facebook account.
Hope this helps!
Ok. Then I suggest that you delete your first account, the one where you signed up with Facebook. Use this contact form and talk to support https://support.spotify.com/contact-spotify-support/
If you receive an email with no reply, you should reply to it anyway. It will take 24-48 hrs before you get an answer after that.
When your old account is deleted you should be able to link Facebook win your new account.
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