If you’ve created a Spotify account and linked it to Facebook at a later date, it’s possible to disconnect the two. Here’s how:
If you want to reconnect to Facebook in future, you can connect it from the same place in your Settings.
There’s more info in this article.
If you don’t see the option to unlink Facebook from Spotify, this means you have a Facebook-created account. The steps for you can be found at this Answer.
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