Balcony construction issue, society formation and conveyance

The flat was purchased by my Father and now he is no more. As per the construction architecture the current balcony is not at its actual east west position.however it is built on north south on ground floor. This was built when the landlord and my father were alive. it was built in 1992. In place of the actual east-west side what i know, the north-south place was marked on ground floor adjoining the flat to be used. My father built a construction of a balcony on it. and its standing there since 1992. The Landlord is no more but his Son is still living there who has made changes to his flat on ground floor and created a new entrance on the east side next to the road. During the rainy season since last 2 years flood water enters landlords flat from the new door.he has come up with fresh arguments that due to my balcony the flood water has a hindrance in moving ahead and hence water logs and increases which causes it to enter his premises and through his door to his flat. He insisted to get my balcony lifted else he will file a complaint and get it demolished. His father had bought this plot from the Society on a lease and handed over it for development to a developer.they also got flats allocated in return on the ground floor and 1st floor.He built a wall fencing in front of his ground floor flat and has been using the area for himself since a decade now.The flood water runs in through the fencing gate and gets in to his flat from the newly constructed door there. Is he allowed to capture the area though he was given proportionate flats for the deal? What will happen if he files a complaint against my balcony in the local corporation office? Also when the building members approached him to get the society formation done, he says he wont allow such society formation and also wont allow deemed conveyance. Please direct in this too.