Goibbo - Complete refund not done

I have booked Air tickets through Goibibo and had to cancel them due to Corona outbreak. I have cancelled the tickets directly with the Airline (indigo) and they have initiated a full refund after deduction of basic charges. They have provided me with a credit note with detailed description of the refund amount and have updated me that this refund amount has been sent to my booking agent/travel website ( Goibibo) and they will do the needful transfers back in my account. When I asked for refund from Goibibo, they refunded only INR **** and showed that the airlines have charged a penalty of INR ****. This is a total lie from Goibibo since the airlines did a full refund and have sent me the proof as well. Now after sending several requisition mails to goibibo to refund the balance, they are neither replying to my mail nor responding on chat properly. It is very clear that they are trying to take advantage of this situation and siphon off the money under pretext of penalty charged by airlines. I would request your assistance in getting back the balance amount in my bank account