Flat advance amount is not being returned by the builder

i paid advance for a flat with Rao & Rao Construction. They cheated me and told me that all the documents related to the lands are available and the loan process will not take time. It's been six months now. since last 3 months i am asking them to return the money but not body is responding properly and going on extending the time. I am not satisfied with their services and i want my return my money back. My friend is also suffering with the same problem from the same builder.