Flipkart — not receiving the product after cash on delivery

Address:

Guntur, Andhra Pradesh

on 9th July 2014 i have ordered an apple I phone 4s with 8gb from flipkart.com as they have told me that the delivery is on 15th July 2014 they called me on 14th July and said that the product has reached the flip kart hub nearest to you, so as i have some personal work on that day i went to the office for the delivery and they took 22500/- from me and gave me the package i got doubt that the package was different from other mobile handsets package i checked the item there itself and there were two stones in it, each and every person there were shocked... they did not returned my payment after seeing this kind of fraud...now what am i supposed to do?