Stuck on ‘For the sick and the injured’ (3/4 machines killed)

There is a part in the mission where you enter a hotel and have to kill four enemies in order to clear the ground floor. I have killed all four of these enemies but I still can’t complete the mission as it says I have only killed 3/4. Can anyone help?

6 posts were merged into an existing topic: “For the sick and injured” bug anyone?