FLIPKART SCAMMED ME WITH FAKE CASIO G SHOCK. How do I get a refund?

Wake up, call flipkart, cry, repeat- this is my life now. I have been in extreme distress over the last 8 days. I received a FAKE/ COUNTERFEIT Casio G-Shock watch from Flipkart worth Rs. 11340/- my hard-earned money. This FAKE watch is coming from a Casio “AUTHORISED SELLER”- RETAILNET. It was an "Open Box Delivery" - during this, a customer is supposed to inspect the content of package and check whether the product is undamaged and then accept the delivery. I checked it and it seemed fine (because it was a very good rip-off the real watch and I had absolutely no idea it was a fake one, the design was the exact replica). Please note, Flipkart app clearly mentions this product has 10-DAY RETURN period. As soon as I received the product and the delivery agent was gone - I went to Casio website to register serial number for warranty. However, to my shock- THERE WAS NO SERIAL NUMBER ON THE BACK OF WATCH. I went to Casio store- where they confirmed its a FAKE watch. Next day onwards, my real struggle starts. I placed return request. However, within 2 days- the seller REJECTED my return request. I received no email, no reason regarding this. In extreme distress, I contacted Flipkart's customer care where a customer care executive advised me to put this return in "Fit issues" category so that the seller does not reject it. I did the same. Waited for 24 hours, return agent came. But he did not accept the return because he has to enter Serial Number on his system and serial number wasn't there on the watch(The VERY reason I am returning it!). I told him the entire story, but he said he is helpless. Result: Return cancelled for 2nd time. I contacted Flipkart customer care again- explained them the entire issue again. They said re-raise the return request and place it in Quality Issues category, I did the same-mentioned the absence of serial number, uploaded all the pictures. After 2 days again another return agent comes-says he cannot pick the item with missing serial number. By this time, I am mentally exhausted to the extent l cannot explain. I contact Customer care again, they start telling me a different solution, I ask them to escalate it to senior manager. Senior manager gets in touch with me - again, contradicts all the previous customer executives and comes up with a new different "solution" - some "Smart pickup". She says wait for 48 hours to get the current return request cancelled, then raise a new one. She also assures she has written detailed 'notes" for the issue so that the next customer executive I call can refer to this and assures that the pickup will be done and refund will be made. I do as told, but after 2 days-AGAIN THE SAME RESULT. No return agent came. I contact customer care again- this time, again, he starts contradicting the last senior manager I spoke to. I ask him to escalate to senior manager. Now this senior manager has no clue and says "we will provide you the 'BEST RESOLUTION POSSIBLE' in 24 hours". 24 hrs passed. Contacted new customer executive. He (Bhaskar) went ahead and cancelled request without permission and asked to wait for 48 hrs to re raise cancel request using the same above reasons for the 6TH TIME! I am exhausted beyond words. They are just waiting for my 10-day return period to get over, my hard earned 11340/- going in drain. Please help me community, how can I resolve this problem?