Flipkart - My phone didn t get returned even after several attempts within the 7 day return period

My order id is OD******************. I ordered my phone on *th of march and it got delivered on *th and after seeing the camera quality I wasn't at all satisfied with it so I opened flipkart and put the phone on replacement on **th of march. The technician guy came saw the phone and said there's no default in phone. The camera is as it is so there is no point replacing the phone and gave a tock mark on no defects on phone. I could see the return option on my Flipkart account so I opted for it and my bank details was asked for the refund. After that no calls no person from Flipkart came to pick up the product and as the return period of * days went off they cancelled my return and now I'm stuck with this phone with poor quality camera. The flipkart executive are saying this phone comes under seller replacement scheme and can't pe returned but only can be replaced and are not ready to listen and putting my calls on hold again and again. This is total harrasment to the customer and I would never like to buy anything from Flipkart after this. I request to see into my matter and help me with the issue.