SE don't really reply to posts here (this is more a players helping other players forum) so I don't recommend waiting for a reply here.

From other threads it suggests the best thing for you to to is ring Future Publishing (number in the mag probably?) and explaining problem to them as with people who didn't get any sheet at all they're sending out replacements so this would likely be similar I suspect. Although they apparently said they only have limited amount of extra codes so probably best not to wait!