Rubber Stamp Maker.in - Amount paid but product not delivered

On **th March ****, I've placed an order for Shiny mini dater _ *X* from Rubberstampmaker.in. Initially, it was showing processing status but suddenly today it's showing "Completed" status. There was no customer care no given on the website. In fact, I've given them a mail regarding the order status on their e-mail id makerubberstamp@gmail.com but not received any reply from their end. Then I found their Facebook business page where I've also raised my query but nobody bothers to entertain me. I've already paid Rs *** through paytm. Neither they have refunded nor they have delivered the product. Tell me what to do now?