Flipkart - the item is under return period but the seller refused to make a return

i order a mobile phone samsung galaxy m** red via flipkart nd i received my order in next * business day. but the phone i ordered is for my aunt and it is not working the way it should be. So i requested for the return and refund/replacement for the order but the seller denied to return/replacement. I already requested for return upto * times within the return policy time limit but they are denying for return/replacement for the item. i just want to return the phone and want my hard earned money back. I did not want replacement because i already tried for that and i am not interested anymore for replacement. I want the order to be returned and mu refund.