Amazon.in - Won't return my package

I ordered trekking shoes from Amazon.in and the size did not fit me. The shoes I received was in a bubble wrap without a box. Now I wanted to return the package but the pickup boy won't take it back saying that the box is missing. I spoke to the customer service but they kept saying that the package will get picked up tomorrow guaranteed. They kept creating the return request but each time the pickup boy kept on cancelling the return request saying that he needs a box. A box that I never recieved. How the hell am I supposed to give them something that I never recieved? They are trying to sell me these shoes forcefully. I really don't know what to do now.