miked

I've Been playing The Halo 2 Campaign, but i haven't been getting the achievements for the levels which didn't bother me because it happened on Halo CE, but then i got all my achievements later on. But now after i beat the last couple levels on Legendary, i went to the main menu and looked at the achievements but it says i haven't even completed the levels at all. does this mean i have to re-do all of the levels again? this is very annoying, wish the would have made sure the game wast ****** up this bad when they released it.