Property dispute

Dear sir/madam, Recently i purchased a plot of 300sqyrds in mahabubnagar dist. Telangana state and i paid advance 10lakhs to him while making bond we mentioned that the remaining amount will be pay after 40 days and make immediate registration. (I take less time because my departure date is very near as i live in saudiarabia) The plot of the owner which he shows me all original documents are genuine. and i check EC from Meesaeva and Registrar office with office seal everything is showing fair.. * MAIN ISSUE: The main thing is the land owner shows patta passbook pahani and make registration to the owner which i buy recently september 2016. But the neighbours said the parents of the land owner have given GPA to the real estate person to make venture and sell In 1995. With total 200 plots approximately. In this venture his son sold some plots with showing patta, passbook and pahani and make registration. So can i take this plot or drop. please help me Iam toomuch fedup with this litgation. Thank you. Regards. Anas