I am having the same problem. What is the solution guys? It worked fine for 48 hours, but won't recognise I have already paid for premium. This really isn't acceptable as we ha e all paid for this subscription and expect to be able to use it. Perhaps I should get in contact with the office of fair trade? Spotify you should reinburse all these people having problem or fix it ASAP!
You started on the 48 hour trial. It looks like the server slowdown experienced a few hours ago affected your transition to the full subscription. Hopefully, this should have been processed now. If there is any problem, log out of Spotify (File > Log out) and log in again.