The new challenges on mcc got reverted to zero when I got on Xbox to do my co op challenge and all the progress I had on PC went to 0
I play just on Xbox, and all my Challenge progress got deleted as well.
I think challenges get reset after every season. Maybe someone from dev or mod team can confirm?
Checked and I have the same symptom. I had played some campaign and got the new skull but yet some of the PVE counters are 0 when they should clearly be higher.
This could be cosmetic though and maybe the actual number is being tracked correctly.