Indian Railway Catering & Tourism Corporation [IRCTC] — Air Ticket Refund Amount not Processed more than 2 Months

I've cancelled the flights tickets on 19th December 2020 from Chennai - Delhi which was booked through IRCTC. As per their policy, they should refund the cancelled ticket cost within 7 to 10 working days but now its almost 2 months passed, there is no proper update from them.
They keep on respond with the same mail template. I've attached the Cancellation proof so please review and help me to sort out this issue asap. Thank you.