Air India - Non crediting of Refund amount in account

Passenger name Nidhi bhargava
TICKET NO. ***-**********
I had booked ticket from Ludhiana to Delhi, for **th May **** but the flight got delayed as I had a connecting flight from Delhi to kolkata so I had no option other Than cancelling the ticket... I requested to cancel the ticket with full refund as one of the option provided by Air India airlines... However on **th may the flight itself was cancelled by Airlines. Till date no refund issued to me as I haven't received any intimation or msg from airlines regarding refund of the amount.
When I enquired from Air India customer care regarding refund of ticket amount.. they told me that the refund was issued on **th May **** but till date the amount is not credited in my account..On repeated conversation customer care agent suggested one thing or another but could not materialise or resolve the issue. When I asked to provide me with transaction number by which refund is issued. they told me to contact on the number of e-commerce of air India to know the refund transaction number as they don't have the same. I also called on number *********** but no one is picking and not getting any reply from the ecommerce@airindia.in