IDBI Bank — a charge back dispute for the refund with the arl referral number-74332749215921446579843

Hello,
I made a transaction on august 1 using my idbi debit card ending with 6126 to pay busindia (Bus ticket booking) for an amount of ₹390. The transaction was made on august 1, 11.13 am. After that my busticket was cancelled and refund was initiated by the busindia team but i didn't get my refund until now, even after 10 working days. I contacted idbi customer care team so many times but they gave me only false assurance that my money will be refunded in 10 working days. I would like to file a charge back dispute for the refund with the arl referral number-74332749215921446579843. Requesting you to credit back my refund to my account as soon as possible.