There is a bug in the LAV that happens when you first appear in the vehicle, which when entering through the front hatch (driver) and you try to switch to any passenger seat and open the door, the character gets stuck, you can no longer change seats or exit. To fix it during the game, you must first enter the vehicle through the rear or by opening and closing the rear doors; it's as if the rear doors are causing the lock while you are inside the vehicle since if another character opens the door from outside, you do not get stuck.