The product code you entered is not valid. Please re-enter the code.

When i try to redeem my game code the code, The game shows up. its the correct game, and ea app knows it. but when i try to confirm that i want to redeem it, ea app says   "The product code you entered is not valid. Please re-enter the code." Does anybody know how to fix it? is it the ea app or am i doing something wrong?