GoAir — Non receipt of refund on cancellation ticket

I had an air ticket from Nagpur to kannur on 28 Nov 20 but unfortunately it was cancelled by Go Air itself and I was being informed that payment will be refunded immediately but I didn't get any refund till now. I have been trying to connect Go Air customer care by teliphonically but couldn't. Very very poor response I got when I sent mail to their authorities too. So kindly I request you to do needful action please.