Thanks for reporting this bug! I will look into it, I believe this is a bug in the actual game, so I may need to rework exits a little bit to fix this.
This bug has been fixed in 0.4 completely as there are new elevators that actually work like Baldi's Basics Plus! I would recommend 0.4.1 since 0.4 has a bug where not all of the elevator doors close when you exit the main elevator.
