Achievement problems for halo ce

My brother and I were playing halo mmc. After we finished halo ce on legendary we did not get the achievement for completing the missions on legenday. We were getting achievements for getting skulls and other things while we played through the missions.
We checked our achievements and it didn't even say we did the mission. Our user names are and twinkiie lord, can you please help us?

:)

 

Achievements still not unlocking

The Maw on Halo CE for me, and so the halo CE completing the campaign achievement isn't working either

 

MCC Achievements not unlocking

Two of the three achievements that I accomplished from the release day unlocked while I was offline at some point. One has not. The two I got were killing 100 jackals and one for completing "Halo" from Halo: CE without entering a vehicle. The achievement
for simply completing "Halo" from Halo: CE is still sitting at 100% "Done! Unlocking..." for me.

It seems like most people's miscellaneous achievements (skulls, terminals, other misc. achievements) have been unlocking over the past few days, but I have yet to see anyone confirm that their level completion achievements have unlocked that were accomplished
on 11/11/14 when Xbox Live was having problems. For some reason those ones have been refusing to unlock.

 

Check your service on Halo - Official Site

 

I am confused because we trying to get the legend achieevment. We are 1 missin away from completing halo 3 on legendary. we got the achievements for completing halo 3 missions on legendary. But for halo ce it says we only completed the first mission. We
did all of halo ce and we even got achievements for finding skulls while playing through but it did not even give the achievement for doing the missions. We do not want to redo halo ce because it was pain to do. It would suck if we had to do it over again.

 

I am confused because we trying to get the legend achieevment. We are 1 missin away from completing halo 3 on legendary. we got the achievements for completing halo 3 missions on legendary. But for halo ce it says we only completed the first mission. We
did all of halo ce and we even got achievements for finding skulls while playing through but it did not even give the achievement for doing the missions. We do not want to redo halo ce because it was pain to do. It would suck if we had to do it over again.

 

If it says you have only done the first mission then you would have to re do it. For some reason if it does not register on the service record on waypoint the mission did not count.