Halo Reach Achievement bug?

So ive completed the whole campaign playing co-op on legendary setting, I have been granted each of the achievements for every mission through the story but wasnt granted ’ folks need heroes’, ‘the soldier we needed you to be’ or ‘the gods must be strong’’ achievement after the final movie?

Wierdly my friend with whom i played through the whole campaign did get those final 3 completion achievement? Anyone have any idea whats gone wrong?

try redoing the las level by yourself then you may get the achievements, i had the same problem with another game, i got the achievement and he didnt . hope this helped you!!

Check each level, and what the completion difficulty for those are, as one may not have been registrered, and the play that level again. Worked for me for a similar bug.