I bought Call of Duty Ghosts for my 360 on Amazon and it came with the Free Fall DLC. When I typed in the code on the DLC card the screen said the code had already been used, even though it was the first time I typed in the code, I tried multiple times to redownload it, on my console, in the in game store, and on the website. It always says the code has already been used. I should also say the game was brand new and shrink-wrapped when I got it, so there's no way someone had used the code before I got it. How can I fix this?