My friend and I are both having our mission progress randomly reset or go back to a previous state. Each match it bounces around, like we'll see 4/10 matches played for a mission. Then after that match it'll say 1/10 matches played. Then next match it'll say 4/10 again. Seemingly random.
We're tracking that issue too. It'll be tomorrow before the team can dive into it. Sorry you got hit with it. We initially thought it was a visual bug since post game seemed to be working fine.