Mast and harbour - Regarding jeans amount not be refunded by myntra

I want to tell of that about myntra was that it hasn’t approved my refund which i had been initiated for my mast and harbour jeans worth Rs *** .They are claiming that brand tag was not there in the jeans and it fails the quality process. First i wanna tell that brand tag was not there with jeans when i recieved it and also i called to the customer care of myntra and told them that I haven’t got any brand tag and also i mentioned there on the comment box when i was returning the product that quality of the product is not good that means it has been used by someone else. I have beeen cheated and they have done fraud. It’s very bad that such a huge e-comerce site will perform like this .