Help! Achievement troubles

Games Halo 5: Guardians
1

So I just completed halo 5 legendary and it says I’ve only completed 93% of the campaign! It wouldn’t be that bad but all the levels say I’ve completed it on legendary so I dont know what one isnt registering

2

This guy recently had the same issue and was able to figure it out. I recommend checking his post for help:

https://www.halowaypoint.com/en-us/forums/e0d9938206f04a598ce84f2c8cadce02/topics/lone-wolf-achievement/5f85e985-0df9-4003-848c-ae1706e52a88/posts?page=1#post5