Municipal Corporation Of Delhi — Cleanliness of water tank

Address: New Delhi, Delhi, 110059

My flat is on first floor and my water tank is on third floor.we cannot clean our tank because of the lady staying on second floor.she don't allow us to clean our tank.it is happening from last 4 years.if any body ask her to go upstairs she started shouting and make mess.we r fedup now and tank cleaning is must now .pls help us to take action against the lady.