After Jill escapes the city on the Subway, you’re placed inside the body of Carlos as he searches for his target. The person here’s looking for is kind of mysterious, but Carlos has to jump through a fair few hoops to make his way through Raccoon City during his search. One of the puzzles blocking his path is a puzzle involving opening a certain locked locker in the Men’s room on the second floor of the police station.
The combination itself is very obvious, as it’s just three letters. The combination can be found on a whiteboard just outside the Operations Room, through the South door. The whiteboard inside this room reads “Locker CAP”. That’s the Locker Room Combination you’re looking for. It’s the same locker and code that appeared in the last game, just FYI.
Head back down to the Men’s Locker Room on 2F and change the combination to match the letters from the whiteboard. This should unlock the locker and allow you to claim the items inside.