Halo 4 reset?

[xi ECL1P53 ix]

After playing the halo 4 campaign on legendary solo for about 6 hours and getting to shutdown, I was happy I was nearly finished and have the achievements and the Mark 6 armour.

 

Though I came on halo today my campaign was reset back to the prologue, though when I look at my commendations, I have finished up to shutdown, it also reset my armour, load outs, season pass content and my rank by 3 ranks.

 

Is there a source or resolution for this problem because I really can't be bothered to redo something I spent hours doing due to shoddy development.

 

If anybody else has this problem please post.