Air India — Air India not refunding since 1 year

Hi,
I had cancelled my AI flight dept 8-Nov-2020 and was awaiting for my refund. I haven’t received it even after following up with them for so many times.Air India claims that refund is processed. I have called as well as emailed them multiples of times that I haven’t received any refund with stamped copies of my Bank statement, still no response from them. How can a Government organization be so irresponsible and dupe its customers
Regards,
Shreyas Rane