the level sensor is located drivers side next to the rear dif. as said. Its about 2 by 3 inch box with a right angle lever/arm connected to a small linked rod with a plastic rose joint on each end. Check the rose joints are still connected/everything is still attached and that the connector is still plugged in and not damaged. If the suspension is rising to full hight you should have no trouble getting under the rear of the car. Its how i use mine when i need to get under the back.
If all is working as it should, when parked in front of, a garage door for instance with lights on, you should be able to see the headlights move when you pop the rose joint off the level sensor arm and raise it, or drop it to its lowest position. The car should move in the same direction as you move the arm. When the car rises and falls the lights should move the beam visibly.
Sounds like a level sensor issue tbh. As the car is high but the lights dont know and are not adjusting accordingly. For simplicity i would concentrate on the selflevel and forget the lights issue until the car sits at the right hight.
If you sit on the rear bumper/boot ledge with feet on the floor while the pump is running you should feel the car rise or fall dependeing. Engine runnings though or youll flatten the battery, it take a while to rise fully.
Have you got "low headlight/field of vision" on the dash display? If not the car thinks the lights are fine.