Sky Holidayz - Forex Amount not refunded

Had booked a holiday package from Sky Holidayz for dates **th -**th Jan and had recharged the Forex card of Thomas Cook recommended by them for INR *****/- The card however did not get activated and I had to pay using my credit card while checking-out from the hotel in Maldives. While we returned from Maldives, we were promised and suggested that we return the forex card back to them and they would refund the money back to my account. So we couriered the forex card to their address below:
Office no *, Sarthak Society Rd, near Bhrama Suncity, Sainikwadi, Wadgaon Sheri, Pune, Maharashtra ******.

It has been over * and half months and we still do not have the money refunded. Despite continuous calls and messages on WhatsApp, we were only promised that amount will be credited sooner but still not credited and our calls were not answered. Though he used to pick the calls when called from sibling's number and again promised that payment will be made but still we do not have the amount refunded. Please help.