Ovantica com - Replacement or Refund

I had placed an order for a mobile phone on Ovantica.com (s** ultra) site description was it was like new and ** check are done. But I received a used product which was opened and imported unit. When I asked for replacement which is one of their policy of * days free replacement, they say they will replace the device but it's been * weeks since I am following up every day with customer support with explaining my problem every day. Till now there is no action. My **k just seems to have gone for a toss and giving it to fraudulent online store. Please help so that this reaches every corner of the world and no one else falls for this trap.