why can't i unlock st.johnson on halo 3 odst?

[Zakk]

I pre ordered the game halo3 odst and i lost the sheet telling me the code. i found it again after 5 days or so and when i type in the code it says please enter a valid code
please someone help thanks

 

[Ry(Fake)]

The only possible explanation would be that either you're mistyping the code or somehow there were two copies of the code you have and someone already used, or someone used your code. There is no way it expired because because it says on the sheet it expires on 1/31/2010.

 

[Gear]

sure youre entering it in the right section? there are 2 and it wont work in one