Would you be willing to answer a few brief questions about PlayStation Forums?
Hello, I bought the game, "Killzone 3", I got the code to release some dlc, but when I put the code that appeared was expired as I bought the game yesterday, what can I do to resolve this?
Sorry but there isn't much you can do since the codes expire. You can try contacting the retailer and see if they'll do anything for you but I doubt it. Typically redeem codes are only valid for one year.