while playing as FireTeam sometimes after changing weapons, shooting / attacking by left mouse button stops working, knife also does not work. When playing as a Predator, attempting to aim with the Shoulder Plasma Cannon performs a melee attack with the Hand Blades.
Switch your weapon and switch it back
I had that issue, several patches ago…
It does not work for me, all what i can do it just restart the match
Try switching with the weapon wheel instead of the key binding.
Man, as I have said before it does not work, I checked all option