Myntra.com — myntra is fraud

I placed an order on 4th april and cancelled it on 5th realising that the sneakers that i ordered were the wrong size. I was told to wait till 15th of april to get my refund. Myntra says they have initiated the refund with the bank. And the bank says they have not received any such refund request. I have contacted myntra several times but they tell me same story everytime. Myntra owes me 4129 inr.