waypoint not updating, legendary run

i am currently doing halo 4 on legendary and i am up to mission 7, but when i check on halo waypoint it says that i have not done level 3 and 4 on legendary even though on my xbox it says i have done them, will i still get the achievement and mark 6 armor if i just leave it or is there a way to fix this

In order to get the armor and achievement, you will need to re-complete the missing missions.

Surely achievements don’t rely on Waypoint to unlock? Keep playing you should get the achievements, Waypoint hasn’t prevented me getting any achievements yet

Waypoint directly reflects your in-game Service Record, which does affect your achievements. So if Waypoint is showing certain Campaign chapters as incomplete, you will need to complete them to unlock any related achievements.

I just completed the campaign last night and got the Mark IV helmet for my avatar, yet Waypoint says I have not completed missions 6 and 7.

I also got the “wake up John” achievement.

It happened to me, you have to redo the missions, perhaps you’ve done those missions when the server fell in a few days, so 'did not save you the missions.