Last week , only three challenges tracked and worked for me, this week a few more work and some challenge will sometimes track but then quickly brake them selves and stop tracking.
I’ll post two screenshots showcasing the issue when you do hit the requirement needed to complete a challenge and then it just gets stuck without giving you the reward and if you think you might fix it by rebooting the game well tough luck, it’ll just remove most of the progress you’ve made in the past few hours of gameplay and set you back, such as me just finishing the legendary play list in Halo 3 in co-op with a friend and having it tell me i still haven’t completed enough playlists after rebooting in an attempt to see if the challenges will get fixed.
Screen shots :
https://steamuserimages-a.akamaihd.net/ugc/1477696391351313342/2A3FD3F4E81DF8D98C6B95BE9A7D3B807BA867EA/