Harassment by developer/builder

I am a doctor and a tenant of a place where I do practice my clinic from more than 32 years. The said building is very old and has not been repaired since last 32 years. My landlord has given reconstruction of the said building to developer/builder in 2011 but since then he has not done any agreement with me. As there has not been done any repair work from many years, one of the tenant’s roofs above my rooms had fallen down and damaged my ceiling and rain water is seeping down in my room. Large quantity of water has collected in the room above my room. As a result of which the water has seeped through the ceilings of my rooms. Due to the seepage the wall and the ceiling had been damaged .The seepage had further damaged the woodwork also. All these had damaged my property and rooms extremely and it is on its verge of getting collapse which may cause loss of life and property. I contacted my landlord on several occasion to repair the building but they had always ignored by saying that they cannot do anything as they have given power of attorney to builder/developer and he has the right to do repairing work of the building and the builder/developer is intentionally ignoring so that existing building gets demolished and he does not have to give old tenants their space. Most of the tenant had left out of fear that the building may collapse anytime. I am also having serious threat to my life and property. I had reported about this to K. M. C and the recently K. M. C had issued the notice to all the tenants for repair. I am ready to repair my portion at my own cost, but developer/builder is stopping me from doing as he had locked the room above my room where roofs had fallen down and water is leaking. Moreover developer/builder has appointed security guard who is stopping my patients from entering my clinic and used to trouble my patient to share their contact details before allowing them to enter my clinic. He always harass me in some or other way. I would be grateful if I could get any advice on it.