Air India — Refund amount not transferred to us

We booked flight for my family of 5 people with Air India for travel on 6/11/2021 from chicago to vijayawada. The airlines canceled the trip due to covid restrictions and they announced the amount will be refunded in full. But the amount was never refunded. The total amount that need to be refunded is $5389.25.
Called the customer service many times. Sent emails and raised many complaints. The air line says the amount was refunded, but they never refunded the amount. They are cheating us. We want the amount refunded
Ticket number and Passenger Names
[protected] —Pradeepthi Appana
[protected] Ritanya Appana
[protected] Sudhir kumar Appana
[protected] Arihan Appana
[protected] Nishita appana