Amma Agricultural land dispute in Kodad Suryapet dist Telangana.

1.My grand father has distributed to my father and to my uncle( babai)each 2acre alternatively from NH-9 so that both can have easement. Proofs: a. A written statement showing respective portions on white paper. b. We cousins and my own brothers again made partition accordingly on stamp paper. c. Accordingly I have registered my portion with sub registrar in SRO Kodad. d. Lease documents e. Sale agreement signed by all concerned. Now my cousin sold my portion of land tortuously by showing old court decree in which my uncle (Chacha ji) had shown to court that 2 acres are sequentially belongs him and next 2 acres belongs us. Due to this torturous act we lost easement and value.This happened in the year 1989 after death of my father and all documents kept with him. Since he is Karta of family we unable to dare to ask the documents. But we were in possession as per proofs since last 45 years. After knowing this we made one family agreement as per proofs. Now my cousin sold my portion by showing court decree hiding family agreement. What shall I do.