No Credit for Completed Solo Legendary Levels

So this is the first time I’ve posted here so I hope I’m doing everything right.

But anyways, I decided to beat all the games on Legendary Solo on the Master Chief Collection. Previously, I’ve beaten Halo Reach, Halo 4 (Regular, not collection), and Halo 5, but decided I wanted to do it on the Master Chief Collection. I started the campaign a long time ago (a year or so) and completed the first two levels. A few days ago I decided to go through and complete it. So as of a few hours ago I have completed Combat Evolved on Legendary Solo. The level select screen displays this. However, the achievement only shows I’ve completed 20% (2 of 10 levels). So I came on here to see what it said; this also shows I’ve only completed the first two levels. I even replayed some of the missions to see if it would update, still I have no progress achieved.
I contacted Xbox support and they told me that I could always just redo it. However, going through all over again does not sound all that fun!

> 2533274816885464;1:
> So this is the first time I’ve posted here so I hope I’m doing everything right.
>
> But anyways, I decided to beat all the games on Legendary Solo on the Master Chief Collection. Previously, I’ve beaten Halo Reach, Halo 4 (Regular, not collection), and Halo 5, but decided I wanted to do it on the Master Chief Collection. I started the campaign a long time ago (a year or so) and completed the first two levels. A few days ago I decided to go through and complete it. So as of a few hours ago I have completed Combat Evolved on Legendary Solo. The level select screen displays this. However, the achievement only shows I’ve completed 20% (2 of 10 levels). So I came on here to see what it said; this also shows I’ve only completed the first two levels. I even replayed some of the missions to see if it would update, still I have no progress achieved.
> I contacted Xbox support and they told me that I could always just redo it. However, going through all over again does not sound all that fun!

Halo CE on Legendary can definitely be brutal, especially levels like Truth and Reconciliation (people blow the Library out of proportion in my mind).

I would say try replaying one of the easier levels on Legendary, and see if it unlocks. Do a little trial and error.