Pagadi tenant rights and protection

Sir Amit here, my original landlord deceased 15 years ago. landlord having 10 legal heirs elder son used to collect rent and then after without any notice his 2nd brother started issuing letters to us to furnish documents such as Aadhar card, electricity bill & last rent receipt also took several meeting for redevelopment and he fail to tk any decision he blame us that we fail to bring up developers for bldg so i reply each letters. As Bldg been more than 30yr old prior 1964 we occupier received notice from BMC 353 B in yr 2019, 354 notice in 2021 and Dangerous bldg banner was stuck in yr 2022 to which we tenants time to time replied the BMC office with earlier audit report that the bldg is not in dangerous stage it can be repair under C2- A continuously giving applications to at least give us temporary permission for removal loose plaster and refill and painting nothing else to stop the seepage After that, we wrote number of letters to 2nd son of landlord who from yr 2021 handling the matter he was given a normal notray power of attorney that time he used to write Jt/owner & POA. Due to his non supply of NOC or any cooperation he forwarded only to me to VACATE the room as it is declare as Dangerous in yr 2022 and after that we again wrote letter to provide NOC for temporary repair he not replied to the same we forwarded quotation of one small contractor he didnt reply then we wrote letter to BMC that we are numerously given letter for issuance of permission bt no reply we need urgent repair which will be no violation of any MMC Act And started the work 20 days ago on ours side. Un sudden 3rd son came and told to stop the work and show us owner permission or BMC to which we told we had communicated to BMC and 2nd son no reply so we to avoid any harm just painted and plaster the loose plaster no alteration or violation then he told me that he will show me so we informs elder son that this incident he told complete the work let them do what they want And last week 2nd son issued a notice stating to vacate the room in 1month as well i have carried out repair work without permission of BMC and landlord i appointed contractor as well no rent has been paid for last many years told to vacate the room or he will take legal action sir, my question is : 1. what steps can be taken to protect room as i have been communicating with BMC and legal heirs but no positive reply to us 2. I have already given chq to elder son in yr 2020 for 3 year bt he fail to deposit i have inform 2nd son to return me the chq and let me know the rent amount i will issue another chq or bank transfer bt no reply to me 3. As 2nd son is targeting to me there are 2 more tenants and one co owner but he is targeting me and issued notice to me no action notices to other tenants 4. As it is G+2 Bldg 2nd floor is not on plan, records or either authorized by BMC due to which no permission is seek to us orally officer told to remove 2nd floor, permission can be is