Cosmos Infra Engineering India — Project of Cosmos not handed over since 2014

Address:

Delhi

I have booked 3 BHK in Cosmos Infra Pvt ltd in Bhiwadi in 2012. Builder Buyer agreement was done on 2014 and in that it was mentioned that project will get handed over with in 48 months. I recieved letter from Cosmos infra in Nov2018 to pay last installment and in that letter it was mentioned for doing registry of the Property.
I paid last installment also but till now Property has not been handed voer to me as many things in project is pending like Flooring, Electrical connection, Painting, Door fitment etc
I visited many times to their office but could not get satisfactory answer from them.
Kindly help me in getting the Property or refund the money.