With achievements having been out for over a decade how is it a major game developer can still have issues with unlocking achievements? It’s just lazy. Halo MCC had a ton of problems and now this game does as well. Mr Punctual, all gold medals, and now receiving a scarab in reinforcement game are glitched for me. Nothing like playing a skirmish match for an hour and finally getting a scarab and then no achievement. WTF??
It is really annoying, I myself have the wall of recognition achievement glitched at 86%, Even though at the top of the achievement page it has a gold medals fraction and it has 15/15 so I really don’t understand how this isn’t working…
I’m still waiting for my code.
I haven’t received a single achievement since the first day I played it. My co-op partner has unlocked them with no issue but despite my attempts to boot into the game each day; complete missions in single player; and hard reset the Xbox, no dice. 
I had this problem, but in order to counter it I simply disconnected my Xbox from all power and rebooted accordingly.
Once rebooted went back and did them again and it gave me the achievements after going over what i already did.
I don’t know why it does this but for my 100 win achievement i had to get 105 because it recorded the 5 but dint put them towards the achievement, so the game stores the data when you look at the information above the achievements but doesn’t count them towards the achievement.
i dont understand how the reboot van help but i ll try
I have same problems 
So far the ones which aren’t unlocking for me are
- Crushed colors
-Ramblin’ Man
-Battened Down the Hatches
-Tour Coming Through
Achievements not on locking is currently a known issue