Water bill outstanding from 10 yrs, BMC didn't cut supply, what to do?

My father own a room in chawl which has a separate water line but the house is unoccupied from last 10 years and the unknowing the water bill is due from 10 years and as of now its current outstanding amount is 12000 INR. So my question is why didn't BMC cut my water connection in the earlier years and went on charging for every year. Am i right that BMC should not charged me even after so much arrears and cut the supply?