Developer Have No Intention To Give Possession...

Dear sir , I had my ancestors property in the form of land and one story old building consisting of about 40 tenants on pagdi system in Kurla west , Mumbai 400070.My father was a share holder which has been passed away. A builder approached to redevelop and had an agreement with me on RS 100 stamp paper duly Notary registered. As a owners daughter I was staying also in the same building. The builder have 3 partners eg A , B ,and C . At the time of agreement A signed the agreement , B was with us also but did not sign as one signatory of partner was sufficient and C was not present at that occasion. Agreement was executed on 20 Nov 2009. Possession timelines was given 3 years in agreement . However the construction is completed in July 2017. Now builder is making a trick to cheat . Partners B and C asked A to disappear and announced that A has cheated them and ran away and now B and C have undertaken the project and will not accept any commitments by A. However the agreement was made in the name of their construction company. In this way he is trying to cheat some people . A is picking up the phone but after asking u the reason and name he says that he is not A and not to call again . Since 5 months he is promising me to resolve but only giving the dates and passing the time.He has given me a security cheque of RS 5 Lac also . Which I believe it's from A s personal account and may be closed account or no funds. Kindly advise me how can I get the possession . Can I get the help or support from the police also . ..Regards.