Adani Gas — extra bill

i paid rs 1000 for registration the gas line fitted wrongly so i complain for line fitting after many call to customer care the line changed but now they sent bill of rs 2500 for bathroom point but my neighbour paid rs 1500 the compny has not solve my problem in time and delay for give gas suply now demand rs 2500 insted of rs 1500 all conection in our socity give same time why different in charge ?