If it's with a certain button (like build mode or the shop button) then your game might be bugged. Others may have this problem as well, especially if it really is a bug. All you can do is wait until EA comes out with the next patch or uninstalling your game and reinstalling (you don't have to delete your save game files or anything when you uninstall). Or, someone else may truely know what's wrong and have a solution for you.