Can not unlock the legend achievement

I have beaten all of the campaign missions from halos 1-4 and it is still not giving me the legend achievement. It is saying I have not beaten halos 1-2 on legendary. I have gone thru and checked each mission on mcc and even replayed a few to see if it would give me the achievement with no luck can someone please help me

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> I have beaten all of the campaign missions from halos 1-4 and it is still not giving me the legend achievement. It is saying I have not beaten halos 1-2 on legendary. I have gone thru and checked each mission on mcc and even replayed a few to see if it would give me the achievement with no luck can someone please help me

Agh! That’s frustrating. Other people have had this issue, and it appears as if there are a few missions the game isn’t registering as complete. Check your service record on Waypoint, and it should be able to tell you which ones it claims you to be missing. Start there.

It said gravemind and high charity didn’t complete along with two betrayals and Keyes. I went back and completed gravemind and high charity but nothing changed.