Yatra Online — Refund of ticket new york to mumbai

Website:

yatra.com

I booked an International return ticket through yatra.com and travelled one way but return travel remain unutilized as flights were shut during the lockdown in July 2020. the airline / yatra promised a refund for the same. my booking No.[protected] about my unutilised New York to Mumbai one way ticket (Ticket No.125-[protected], PNR:S433ID) due to non operation of British Airways in the month of July 2020.
since then I have been following up by numerous calls / emails for the refunds but they have been asking for more time every time.. they have taken my cancelled cheque with all bank details and have verified all details as much as possible but all for just passing more time.
last email they sent was in July 2021 asking for 45 to 60 days for the final refund but till date I have not received the amount.