HappyEasyGo — refund amount not received

I booked my ticket from these travel agency ( happy easy go) on 25th oct departure terminal from Delhi to agartala.My ticket was booked successfully and payment too, , through which the transaction was done by debitcard..i received the booking id confirmation through messages and emai and everything was right..later after an hour and a half i got a phone call from customer care replying that my booking was cancelled due to up and down in the airline fare ..i was shock to hear ...then i ask for the refundation replying that the amount will be refunded within 10-15 days..till now they are not in condition to cooperate with me regarding my refundation...more over they are unable to provide me a satisfactory explanation for the cancellation...