Thanks for posting, that is an unusual one. I'm not sure if it will help but could you run the repair function from the launcher to see if this makes any difference.
Exit the game and open the launcher again. Login as normal but do not press play. When the play button appears click on the cogwheel in the left corner of the launcher and select repair.
Once the repair has completed, click play and see if the problem has been resolved.
Let me know if this helps.
Unusual? The problem has been reported multiple times on the forums, and none of the recommended fixes solve anything.