Litigation plot sold..

Dear Sir, I am Sunitha from Hyderabad aged about 33yrs.. I purchased a plot in Secunderabad near Dairyform Road , Tirumalagherry 159 sqyards around 16600 per 2012 June.. Plot is in Litigation main property holders are 2 persons and one of the person in that sold out the property by deviding in to different plots.. Now the other person already filed a case in high court and the case is in existing.. One of the person who sold to another person and we purchased that plot from that person.. Now I recieved affidavit mentioning that I am constructing the house which is already in existing court case.. I should attend high court regarding this issue... I already approached one advocate and he is filing case to return.., now my query is I don't know that property is under Litigation and without knowing I took EC from ESeva and I got clearance from EC.. Then I purchased the property.. Now how I can take action against the person who sold me property without informing us that the property is under High Court.. How to get back my money.. Kindly give me solution..