Hey guys i just completed halo 4 on legendary, i got the achievements for it and i went through all my missions and there complete. But when i go into my commendations for campaign it says i havnt completed 2 missions therefore i didnt get the legendary armour and visor. HAs this happened to anyone else if so how do i fix this problem i tried signing out then back in but it didnt do anything 
please help
Its happened to people (not me tho), you have to do those missions again in order to get the armour.
I think you have to be connected to Xbox Live when you do them. It is a common problem and your not the only one who experienced it.