GoAir — GoAir cancelled the flight but did not give the ticket refund

Hi,
GoAir canclled their flight G8283 stating reason of some unavoidable issues due to ongoing pendemic.

The flight schedule was: 12th June 2020 at 7.25AM
From Pune to Nagpur (non-stop)
Please find the attached ticket.

Even though they cancelled the flight, they have not Processed my refund.

I have tried communicating with them on all the customer service number shared on their official site as well as I have dropped follow emails multiple times to their escalation ids.
I could not receive any response.

The refund amount is : Rs. 8708.00
Additionally I have paid extra amount to book seat before web checkIn.

The ticket was for two adults :
1. Puja Anil Marliwar
2. Pradhyumna Anil Marliwar

PNR: DBYIRA

I need full refund in my souce payment method.
It seems they are unwilling to provide support to customers.