Hi, and welcome to the community!
If you signed up with Spotify in the first place, then you can go to Edit>preferences then disconnect from there.
If you originally signed up with facebook, it is a little more complicated.
1) Firstly, you should create your new account with Spotify rather than facebook.
2) Then you can submit an online contact form; and someone at Spotify should be able to move everything over from your faceboook to your new Spotify account.
If you get an automated reply; make sure to reply to it directly (even if it's from a no reply); and it will be sent to the Spotify staff.
3) You can then deactivate your facebook account.
Anthony 🙂
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