Air India — Refund not received even after 1 year

My flights from Frankfurt to Delhi scheduled on 27th Mar and Delhi to Frankfurt on 13th April 2020 were cancelled by Air India due to the ongoing pandemic. It's been almost one year and I have not received the refund until now. I have written Air India multiple emails but haven't received a satisfactory response.

Given the current situation, I do not have any near term plans to travel to India and hence would like my complete refund ASAP. Thanks!