Do everyone having a same problem with me?
My melee doesn't work after i die once in campaign mode.
I try to change my key setting, but the problem doesn't fix
It even don't show the option Stealth kill or power kick anymore, that that svck for a stealth player like me

Just don't die....
I had the same issue through the campaign, had to restart the game when it happened.
I have not heard of a solution yet.