possible Rank reset fix

level up to rank 4+, and swap around each perk in each custom class slot. Once all of the perks are non-default, log out, wait 30 minutes, then log back in and see if it's fixed.

if this fix didn't work for you or you don't wanna do the fix you can try to contact @PCDev At Twitter they're the *former* cod developers on pc for treyarch or contact activsion support on twitter at @ATVIAssist