helioskrill armor

ive beat all the campaigns in the MCC and halo 5 on legendary but it doesn’t show it on here and also I never got the helioskrill armor
who do I talk to or where do I go to get this straightened out

I did a quick check of your MCC history and you have not completed every campaign mission on Legendary, neither on single player nor co-op (you are missing progress in Halo CE and Halo 2). You’ll need to go back and play every mission again that isn’t logged as completed on Legendary, either co-op or single player. Sometimes, for whatever reason, the game doesn’t register when you complete a level. This happened to me a couple times; all you can do is replay the level. Also make sure that you don’t have any skulls on that have a 0x modifier; these “easy mode” skulls can nullify the unlocking of achievements.
(Your “Legend” achievement, which is the achievement that unlocks Helioskrill, says you are 75% done)

I guess it would be the 0 modifier skulls because in game it shows all missions completed on legendary (that’s different than what is shows here)