Arjun Dhulap

I have a lexus lx470 2002 year model but suddenly the AHC stopped working for example when i go the raise the height the AHC light blinks that it goes on high but the car neither does climb it just stays at (N) i need some help cause the car just recently came back from servicing and this started happening i took it back to the dealer ship they reset the suspension actuators but one day later the same thing happens . plz help me