It has been reported to us and confirmed locally there is an issue with
stats not progressing after matches are completed. The team is looking
into this issue now. You can monitor this thread for more information as it develops: https://forums.tripwireinteractive.com/forum/killing-floor-2/kf2-news-and-announcements/news-and-announcements-af/2333521-xbox-stats-progression-issue
There is no longer a need to put in new support tickets on this issue.