Let's try following this troubleshooting to make sure you don't have multiple Spotify accounts that could be causing this.
If you're sure you have the correct account, try logging in here, and head to Subscription, you'll see if the Premium service is up and running. In this case, you can try reinstalling Spotify on your device.
Let us know how it goes.
“Music acts like a magic key, to which the most tightly closed heart opens.” ― Maria Augusta von Trapp