Cheat codes disable the ability to earn trophies. if you are going to use cheat codes first turn off auto save and never ever save the game with a cheat code activated. Otherwise you lock your self out of being able to earn trophies when using that save file.

The only way to overcome this if youve already saved is to start a new, uncorrupted game save. (start over).

this is not uncommon in games. in fact the most common trophy block is changing the difficulty mid game. the age of cheat codes is fading. less and less games offer cheats. Instead, alterations like new costumes, extra money or experience, or different game modes are instead being offered with a price tag and disguised as DLC or pre-order bonuses. If you have access to the PS Store look at the DLC for Madden 10. Things you used to be able to earn for free and use whenever you wanted now have price tag and are only able to be used once.