Zivame — Refund not received

I have purchased 3 sports bras from zivame. From which two out of three i returned due to non fitted. But when i asked for refund they told me that it will take 15 to 20 days to refund as they will get the confirmation from the warehouse. Now more than 20 days have been passed, but they are not interested to refund the amount of those two items. They send me same response everytime whenever i asked for my refund that they are waiting for confirmation. Rs. 243 and rs. 348 due with them.