Seepage issue and misbehavior of flat owner

Hello Sir/Mam, I hope you are doing well and safe ! I would like to draw your attention on the issue which I am facing from last 3-4 years. This building is situated in East Delhi. I am livin' at 2nd floor. From last few years I am facing seepage issue from the upper flat washroom. I have informed flat owner so many times but he and his family are not paying attention to this issue. Everytime they behave rudely and Badly whenever I go to them to convey to fix this issue. There is continuously draining of water from upper flat and because of this seepage issue my house is starting smelling badly. I have already send him the images of my home but they block me from everywhere and everytime they say they will fix it but no one comes to fix it. They blame other flats responsible for the seepage on my home so that they have not spend money. There tenants are staying in that flat and this flat owner staying somewhere else.Could you please help me how can I get rid of this issue as this is causing loss to my property and giving me major headaches. Thanku so much for ur advice in advance !