Legendary Campaign issues; unsaved progress?

I need your help 343 im doing my best to relive my chil here with this game on Legendary but everytime I check my progress it is saying unplayed and we beat each level! only some save but it took my cousin and I too long to beat Halo:Combat Evolved because we would replay the missions so they would come up! now the same problem is happening for Halo 2, please 343 fix this! Fix the problem with each completion you get a progress update! please it’s depressing, especially the challenge of Halo 2 on legendary, it’s fun but frustrating to not see your progress being saved… I’m on level 6 as the arbiter and it says I’ve only beat the Amory tutorial, nothing else? I’m getting my achievements but I want 100% completed… Understanding my cousin and I’s frustration, please fix this problem!
Sincerely Hardcore fan GTs: ThatGuy0vrTher & That0neGuyJesus
*Mark Rojas