Amazon - Package not delivered

I had ordered for a lenovo tab ***-*******-******* on June *. It was supposed to be delivered to me on June *. Since I had multiple orders on that day, amazon cheated me. The delivery agent came with * parcels. I had * health mix powder to be delivered to me on that day along with one tab. The delivery agent came with one cardboard box and another bubble wrapped package and asked me for the OTP. The package looked similar to a tab so I disclosed the OTP and got my order. I opened the package and found health mix powder inside the cardboard box and another health mix powder bubble wrapped. But from app they had changed the status of * health mix powder and the tab as delivered while I got only * health mix powders. Pfa the so called tab but a bubble wrapped health mix powder. I raised a complaint with amazon customer care. Since amazon is a huge company who keeps track of their customers, they would definitely be having the backup of all the chat I had with the customer service. The customer service chat person asked me to wait until June *. I waited until June * and raised an issue again with amazon, they said they are raising an investigation against this issue and cleverly asked me to wait until June ** as June ** is the last day for replacement or refund. I waited until June ** to find out that the delivery agency claimed to be delivered. As a customer I trust amazon and book items from there. Now amazon claims that they are only an intermediate and not a seller or a manufacturer. But isn't that amazon's responsibility to satisfy their customers. Seller of a health mix powder and a tab are obviously different. A tab seller isn't going to pack a health mix powder instead of a tab. So the problem lies with amazon packing which they don't accept. They failed to give me refund or deliver my ordered item. I am a very disappointed customer who has saved money for almost * months to gift this tab to my mom. But unfortunately I did not have the cardboard box in which the order I'd was mentioned. So they closed the case saying that the order has been delivered. And now amazon cannot do any further investigation on this itseems. Don't you trust ur valued prime customers?