Complete Halo Achievement Won't unlock for me.

So when I first got the game one of the first things I did was play Halo CE. After beating the second level I didn’t get an achievement. It said Done unlocking on the bottom but it never did and it still won’t. Does anyone else have this problem? Also will 343 see this?

Have the same problem with 4 or 5 Achievements but i dont know why :confused: hope that 343 fix it.

Completed halo 2 and 4 legendary, no achievements for some levels, none for completely the campaign even on easy, let alone on harder difficulty’s, really needs to be fixed!!
I’ve tried reconnecting to internet and checking server connection, given it a week now, also switch it off fully and still nothing just keeps saying the same three movies are unlocked

[deleted]