If you're trying to log in to your own account through Facebook but seem to be logging in to a family member's by mistake, no worries!
This can happen as Spotify can be automatically logged in to a Facebook-linked account on the default browser of the device.
In that case, make sure to try these steps:
Go here: https://www.facebook.com/settings?tab=security§ion=sessions&view
Make sure to log off of every session you'll see on that page. This will log you off from every device, including smartphones etc.
Open a new tab on your browser (if you're trying to access the Web Player) and try logging in again with your own account's credentials.
Alternatively, you can make sure to clear the browser's cache and sign out from Facebook, then try signing in with your own login details again.
This Spotify Answer was submitted by @papayawhip and @Loxer.
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