I just finished the game on Legendary Solo but didn’t get any of the following achievements (Legacy, Heroes Rise, Forging a Legend, Lone Wolf)
The progress on these achievements says it’s only 93%
I tried to finish another mission and tried to hard reset my Xbox but the problem not solved.
Please help me 
Have you tried a hard reset?
Re-directing to the Guardians Support forums
https://www.halowaypoint.com/en-us/forums/e0d9938206f04a598ce84f2c8cadce02/topics/achievements-not-unlocking/ea238265-7898-42fa-b929-153ad7d345fe/posts?page=1