My SCW-10 hasn't been unlocked even after completing the challenge

Hi there,

For a while now I've had the SCW-10 challenge done but my gun is not unlocked on the load out screen to use. I've tried restating the game multiple times. I've also tried repairing game files as i'm on the steam PC version of the game. I've even looked up and tried doing the challenges again for the unlock and playing a full game of multiple game modes and the gun still isn't unlocked. I have provided screen shots of my challenge screen and my load out screen to prove this. If someone could contact me and/or sort this bug out so I could use the gun, that would be greatly appreciated. 

Thank you for your time.

Jake - BatyTC