Flipkart.com - Wrong Product Delivered Refund Denied

I ordered a Redmi Note ** on *th April **** (Order id OD******************). Upon delivery I received a Redmi * Pro. I put up a return request, provided all the necessary documents such as id proof, product images and a consent form for filing an FIR against the missing product. My return got approved on **th April ****. For * days, no delivery agent knoecked on my doorstep or contacted me for the pickup while I kept receiving Ekart delivery alerts. Then he visited and refused to collect my order stating that he was supposed to pickup a Redmi Note ** and not the product that I had received. I tried explaining to him that my return was placed for a wrong model only but he misbehaved and left. Then the seller cancelled my request on **sr April ****. Flipkart customer care keeps postponing resolution date, when I tell them to connect me to the senior executive desk my calls are continually dropped. My money is still not refunded.