Hey @mwiederspiel,
If restarting the phone as EA_MAI suggested doesn't work, which it should in most cases, then try uninstalling and reinstalling the game. Now the most important part of this procedure is what you do first, and that is to save your game on Facebook or Google Play or on whatever server base your game is operating off of. Then go to the store where you got the game and look it up. It should have an uninstall option instead of an install option, select it. After your phone has gone through and finished the procedure of uninstalling the app, restart your phone to clear out any stray files. Now reinstall the game by the same method as you did before but make sure it is exactly the same game. Once this is done, open the game and you will see it start up as a brand new game. DON'T PANIC. Once the game has taken you through the training it will get to the point where it will ask you to name the game. BE SURE to name it THE EXACT SAME NAME AS BEFORE! The server will recognize it as a duplicate and ask you which you want to do, continue the game as is or load the saved game which you will recognize due to the skill level being the higher of the two.BE SURE TO CHOOSE ONLY THE SAVED GAME AS THE SERVER WILL DELETE THE ONE YOU DON'T CHOOSE! After a moment or two you should be back in your old game playing it glitch free as it's a freshly installed game. Of course this is a last resort as anything could happen during this process that could trash your game so be very careful not to press the wrong button or drop your phone or anything like that.
Good Gaming
JAGrossman
