Amazon India — Return and Refund scam

I have ordered Redmi mobile on 12 August and I receive on 15 August. While using the mobile it has some problems I have raised return compliant they have checked using their online application. And accepted there is an issue in product. The they arrange for retun pick up. But the 1st return pickup is failed due to imei no mismatch this itself delayed and 2nd pickup also failed after contacting customer service they reschedule 3rd pickup by ECOM Express on 19 August and it was successful and the item reached the seller on 21 August 5.30 pm. Till now I have not received my refund Amount they have not initiated or process my refund. My Amazon account tracking show your item is pickup up once we receive the item refund will be process. This is on 25 August. When I asked customers support about the tracking issue they simply saying website errors. When I asked about my refund status they saying me to wait another 4 working days.. they are not even processing my refund till now 25 Aug