Radha Traders - Received fake mobile phone

I have ordered a Samsung Note * at ***** at COD from the Radha Traders. They open OLX account in the name of Astha their phone number is +************ and their address is in Chennai. But after contacting her and speaking to her several time I accept and decide to buy. She said that she can't meet in person and told me that she will be sent through courier. After she sends the product I came to find out that the phone was shipped from Delhi. After seeing this I again call her up and asked for the authenticity of the phone in which she said to calm down and not to have tension. Then after * days, the mobile was delivered and I insist to check the phone before paying in which the seller and the courier person declined. Then I have no other option but to pay and after paying I opened the box and came to found out the phone is actually fake Samsung Note * which is not I have ordered. I have ordered genuine Samsung Note * and they send fake Samsung Note *. After this, I called them and asked for a refund and they said ok and when I asked them about the details process to return they didn't pick up their phone nor reply my messages and later switch off their phone. Kindly look into this matter and help me refund my money.