Rerolled Challenges Not Tracking

I rerolled a few of my BR-related challenges to MP-related ones, and those same rerolled challenges are tracking very inconsistently. 

Assault Rifle Kills+Assists /50 - Only tracks once in a while, and sometimes not even in the same match despite using the same AR the whole round.

Win Matches in any mode - I've only had it register 1 win out of multiple so far.