Stentorian Brake Muzzle Bo7 Bugged for Mammoth & FG42

Please Treyarch Fix this stupid bug, out of the 6 people I played with last night 3 of my boys are able to use it and then me plus my other 2 friends can’t use it can we just fix this please it’s saying I have to unlock in armory when I use it on literally every other gun because I’ve had it unlocked since it came out… anyone else having this issue seems like half of the community can use it and the other half can’t. Unfortunately I am one of the people that can’t and shit like this should be fixed in a few days from the guns releasing should not have to wait until mid season update for that to be fixed come on treyarch can’t be that hard to do!