Thebigmart.in - Counterfeit product delivered

Hi, I have placed an order to buy a Bluetooth speaker made by the Brand “bose”at www.thebigmart.in couple of weeks ago. Post submission of the order, I haven’t received any email confirmation or sms confirmation. A week later I have received the package through delhivery courier under cod basis for Rs.****/-on **th Feb, ****. The seller is newgen digitech india , Sharad Vihar, Karkardooma, Delhi-****** and the return address is the same. There is no contact number kept on the address. I have paid the said amount as cash and received the package. After I opened the parcel, I understood the item is a counterfeit one of BOSE Bluetooth Speaker. I tried, contacting back to the website address, no response and the phone numbers are not working. Today I have checked the website, but the page is not working. I have not recorded their address during the purchase. I really stuck, need your help to get refund from the seller and I am ready to return the item.