Consumer Redressal

Eight months back I planned to buy a plot near chennai.I saw a advertisement from real estate organization.So I approached them and they also showed me a land and explained me the details.So I also thought it as good to buy it and they wanted to to pay the advance amount of Rupees 1 lakh for booking the plot.So I payed the amount 1 lakh to them.After few days,they asked me for another 1 lakh for buying the registration document.So totally I have given 2 lakhs to them.While nearing the registration date,the real estate person called me and told that the land I have booked is not available for sale,and asked me to buy another land,which is not that good.So I told them that I dont want that new land and asked to return the money.Still now,they have not returned the complete amount.They have returned only 93 thousand in the form of 43 thousand as registration document and 50 thousand cash they transferred into my account.Please let me know,What I need to do to collect the remaining amount.