HDFC Bank — credit card transaction dispute not resolved even after 1.5 month

I did a pos purchase with my credit card on 17th june 2019 of rs. 5, 415.00. The same is reflecting in my june month statement, however the same has not been credited to the beneficiary account. As a result i had to make the payment in cash.

I raised the transaction dispute attaching the cardholder dispute form along with the bill of the cash payment for the transaction on 24th june 2019 to cc. [protected]@hdfcbank.com and customerservices. [protected]@hdfcbank.com as advised by the custom care professionals.

Query reference number for the e-mail: [protected]
Hbl=[protected]

It has been more than 40 days with no update. When i am calling customer care professionals, they have no update on this and i am just being asked to wait, somebody says for 2 days and someone says 90 days.

I have already sent around 10 reminder emails and at-least called customer care 5 times.

Is there any way i can report this to rbi?