Myntra.com — Money in cashback

Hi, I would like to file a compaint against Myntra.com. I had Rs 1496 in my Myntra cashback account. My account was logged in through facebook, and due some unavoidable situations that account is disabled. I called customer care of Myntra and they told me to email us your new account where you want it to be transferred now. I sent the same and got reply that it is not possible. I am ready to provide them all the details of both my myntra accounts with my address proofs. But still, they are not giving me my money back. For simple login they have forgot paasword, but they should also have some recovery for facebook accounts also, if they have facebook login on their website. Neither it written anywhere in their policy for such situations. Please help me out. Waiting for a positive reply.