Homeshop18
Wrong product delivered and not refunding

I ordered a Olympus camera

http://www.homeshop18.com/Olympus-FE47-12.1-MP-Digital-Camera/Camera-&-Camcorders/Digital-Cameras/product:213569/cid:3183/catalogueID:2/ . I got the wrong product. I had ordered a 12 mega pixel lithium Ion camera and I got a 14 mega pixel non litium ion camera. I complained and returned the camera on 3-mar.through TNT AWB - 283872825 (homeshop 18 Official courier). after lot of followups they claimed that theyforst claimed that they have not recieved the product. after I gave them the proof of delivery they now claim that they have recieved a VOX mobile phone instead of a camera. Now I am stuck with the lack of integrity and work ethics of Homeshop18. need help.. I paid in advance and I stand cheated.