Car Parking

I stay in mumbai and have purchased a flat in aurangabad from a builder. Now the society is formed and I have given my flat on rent. Builder has not mentioned the parking number in the agreement but he had alloted a parking to each member by mention the flat number on the stilt parking. One of the member staying on 1st floor is removing my flat number from the parking and parking his own car and not allowing my tenant to park the car. Comitte members and builder are not taking any action against him. So kindly advice me, where shall I lodge a complaint.