"Weapons Specialist" not unlocking

[YairGOW]

So I'm playing this game is couch coop and all of the trophies that should have unlocked up till now have been unlocked, except for "Weapons Specialist".

We have both maxed out the rifle's rate of fire, power and clip size as recommended in several guides, but for some reason it won't unlock.

We will try maxing out the other weapons, as well, in hopes it works.

 

Did anyone encounter this issue by any chance?

 

Edit: I managed to get it. Seems like the reason it wouldn't unlock was because I accidentally played through mission select instead of campaign. 

Edited November 11, 2020 by YairGOW