Forza motorsport 3 problem?

I have just purchased Forza 3 from a game shop in chippenham, I got the collectors pack which comes with a "game add-on content" sheet, which basically has a code on it, which when entered into the redeem code part of marketplace gives you 10 legendary cars from the first 2 games and 18 tracks, the problem is when i enter the code it says code not valid, does this mean tht someone has already used tht code?, the code is protected by the scratch off silver stuff so i dont know how they would have. what else could be causing this?Forza motorsport 3 problem?
It could mean it's already been used, but that's not very likely. It's more likely that you've typed it in wrong; double-check the code, especially things like 8s and Bs or other numbers/letters that can look the same on the card. You can also try redeeming it through the Web marketplace (http://marketplace.xbox.com) to make it easier to type in.Forza motorsport 3 problem?
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