my neighbours not paying property tax since three years.(commercial building, G+1, collecting rents 60k per month.). owner age is 95years. building age is 50years(constructed without pillars support).currently the building condition is in very dangerous condition and likely to collapse @ any period of time. one month before GHMC issued notice under section 459 of HMC act.But till now GHMC has not demolished the building. What should i do...?