Halo 3 MCC PC Achievement/Waypoint Not Registering

Games Halo: The Master Chief Collection
1

Hi I’ve just completed the mission “Cortana” on Legendary from Halo 3 MCC PC.

It took me 2+ hours (I’m a complete beginner) to finish it and it didn’t trigger any achievements on steam. When I checked Waypoint, it also states that I have not yet completed the level. Is there any way to correct this? It’s frustrating to have spent all that time for nothing.

Thanks

2

Its ok, I just replayed the level and got it

3

bump, same thing happened just now on The Ark with me. I don’t want to replay it again cause it wouldn’t be enjoyable!