Happyeasygo - Cancelled Flight Ticket Price not refunded

I booked a Flight Ticket of Indigo Airlines through HappyEasyGo site from Kolkata to Delhi. My date of journey was ** Dec ****. (Ticket Attached) But, due to reschedule of Airlines I have to cancel my ticket. Owing to this, concerned Airlines have offered me full refund opportunity. Subsequently, I applied for cancellation & refunding of ticket amount to HappyEasyGo as well as to the concerned Airlines. Details of the tickets are as under –
• Flight – Indigo *E***
• PNR – URBG*N
• Date of journey - ** Dec **** from CCU to DEL (Time : **:** to **:**)
• Order Id – ******************
• Order date – **/**/****
• Total price – Rs. **,***/-
• Applied for cancellation on **.**.****
• Reason for refund : Flight was rescheduled by airline.
*. As per standing norms, mentioned at HappyEasyGo website, it takes **-** working days to complete refund process. But, after surpassing of more than SIX MONTHS, HappyEasyGo has not refunded my ticket amount. In this regard, I have contacted with the concerned Airlines. They have replied that the refund amount have already been returned to HappyEasyGo in time. I have also contacted HappyEasyGo customer care over phone (Ph No. **********, **********, ***********), twitter handle (@happyeasygo) & e-mail (cs@happyeasygo.com) . But, they have not attended my calls, my request over twitter handle & e-mail have never been responded.