LEGENDARY CAMPAIGN WONT COUNT!

I am having the most annoying problem here on Halo: Master Chief Collection! I have played Combat Evolved on legendary but when I check the missions on the main menu not all of them count! It says I haven’t played some missions even though I have. This gets super annoying because it takes forever to complete them over and over until it finally says “completed on legendary” Im trying to get the Helioskrill armor for Halo 5 and to do that I have to beat CE, 2, 3, and 4 on legendary. Please fix this 343 or let me know what I can do to fix it.