#2, pull the headlight. If you're lucky the adjustment screw just backed out of plastic holder and away from the gear. Just push it back in.
If you're unlucky, the gear is stripped. You can still adjust it using a 10 mm wrench with the headlight out of the car so it's an iterative adjustment. Best to raise this headlight and then reinstall and adjust the other one to match.
If you're really really unlucky, someone backed it out all the way and the ball popped out of the headlight bucket socket. You'll need a new headlight or need to remove the lens to correct it.
Sorry for the revive but I had to offer my fix in case anyone else gets in this same predicament.
I had also backed the ball joint out of its socket.
So I removed the grille, headlight, and back panel, saw my blunder and realized I needed to get that socket back on the ball. .
I turned the adjustment screw as much as I could, lowering the ball as much as it would go, and grabbed the metal housing lip in between the two headlights with some needlenose pliers, and gently pulled the housing back untilI heard/felt the "pop" of the socket rejoining with that ball joint.
I checked the adjustment screw and it was working as it should!