Help! Completion not showing in Halo!!!

Hey all,

Apologies if this is already an answered question but I couldn’t find anything about it anywhere.

I played Halo CE with another Xbox live user at his house and completed it in full in about 13 hours and we were chuffed but we noticed that we didn’t get the achievement for doing so but had gotten all of the others. I went home and turned on my copy and signed in to find that my halo did not show that I had completed any of the levels except the library. I checked with my mate and he said his Xbox showing him as completing all but the library.

I really have no problem with having to slog my walkthrough this on legendary again but I feel robbed and was wondering if there is anything that 343 might be able to do to help. I have all of the achievements on my profile to show for my efforts but would also like my profile in the game to show I have completed this.

Thanks in advance
Grim
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