I have finished every game in mcc on legendary (some multiple times). I have double checked each game mission by mission and every mission in every games shows: Level Completed: Legendary.
I’ve received the achievement for each individuals game being completed but the Legend achievement will not unlock. It sucks that its listed as one of my “near completion” achievements but it’s done!!!
I’ve had MCC since it’s release and this achievement not unlocking is super frustrating.
Anyone have any help?
According to your Service Record you have not played any Halo game on this account. If you could provide the gamertag you are using the Community may be able to help you.
> 2533274809226598;2:
> According to your Service Record you have not played any Halo game on this account. If you could provide the gamertag you are using the Community may be able to help you.
Sorry, that is an old account. I’m now logged into the correct one. - thank you for noticing that.
So if you look at my gaming history it says I’m 12/13 on H2.
On my console it is complete.
H2 is my second favorite of the games and I can tell you that over the many years, I’ve played through H2’s legendary campaign multiple times.
Anyways, again it’s super frustrating that I can’t unlock this achievement due to this weird glitch. 
> 2533274803065511;3:
> > 2533274809226598;2:
> > According to your Service Record you have not played any Halo game on this account. If you could provide the gamertag you are using the Community may be able to help you.
>
> Sorry, that is an old account. I’m now logged into the correct one. - thank you for noticing that.
>
> So if you look at my gaming history it says I’m 12/13 on H2.
> On my console it is complete.
> H2 is my second favorite of the games and I can tell you that over the many years, I’ve played through H2’s legendary campaign multiple times.
>
> Anyways, again it’s super frustrating that I can’t unlock this achievement due to this weird glitch.
Unfortunately it is what appears on here, rather in game, that counts. According to your Service Record you need to play through The Great Journey again. Completing it again should sync the data.
> 2533274809226598;4:
> > 2533274803065511;3:
> > > 2533274809226598;2:
> > > According to your Service Record you have not played any Halo game on this account. If you could provide the gamertag you are using the Community may be able to help you.
> >
> > Sorry, that is an old account. I’m now logged into the correct one. - thank you for noticing that.
> >
> > So if you look at my gaming history it says I’m 12/13 on H2.
> > On my console it is complete.
> > H2 is my second favorite of the games and I can tell you that over the many years, I’ve played through H2’s legendary campaign multiple times.
> >
> > Anyways, again it’s super frustrating that I can’t unlock this achievement due to this weird glitch.
>
> Unfortunately it is what appears on here, rather in game, that counts. According to your Service Record you need to play through The Great Journey again. Completing it again should sync the data.
I’ll give it a try.
Thanks for responding.
> 2533274803065511;5:
> > 2533274809226598;4:
> > > 2533274803065511;3:
> > > > 2533274809226598;2:
> > > > According to your Service Record you have not played any Halo game on this account. If you could provide the gamertag you are using the Community may be able to help you.
> > >
> > > Sorry, that is an old account. I’m now logged into the correct one. - thank you for noticing that.
> > >
> > > So if you look at my gaming history it says I’m 12/13 on H2.
> > > On my console it is complete.
> > > H2 is my second favorite of the games and I can tell you that over the many years, I’ve played through H2’s legendary campaign multiple times.
> > >
> > > Anyways, again it’s super frustrating that I can’t unlock this achievement due to this weird glitch.
> >
> > Unfortunately it is what appears on here, rather in game, that counts. According to your Service Record you need to play through The Great Journey again. Completing it again should sync the data.
>
> I’ll give it a try.
> Thanks for responding.
You’re welcome 
Let me know how it goes.