Property dispute between true brothers over their father's originally owned property

If A and B are true brothers and their father was original owner of a property and after his death the property was transferred to their mother and after her death the property was transferred to A alone without any registered aggreement or release deed of B by some unknown fake and forged documents and now the society only recognises A as a lawful member without showing the registered release deed of B on said property and not cooperating with B in any way whatsoever. So now in order to safeguard his legal rights in said property B has taken possession of the said property and was paying the maintenance charges for a considerable amount of time. But now when B demanded a simple NOC from the society, the society has denied to issue it to B saying that it doesn't recognise B as a member inspite of knowing that B has been cheated and the property is transferred to A alone without the aggreement or consent of B and society is not replying to emails of B repeatedly questioning about showing documents on the basis of which property was transferred to A. B maintains a stand that B would pay maintenance when property is transferred to B's name. A is pressuring B to pay maintenance. What should B do now?