Citibank — CITI card [protected] purchase on 8th June'22

Address:

2nd Floor, No4, National Convent road, ISRO Layout, Vittal Nagar, Bangalore-560078

My son used my CITI credit card number : [protected] - Master card, for purchasing international tickets from London to Bangalore and back, on 8th june, 2022, through BravoFly booking ID:[protected].
Initially ticket price shows during checkout as : Rs.2, 08, 423.39 (In Indian Rupees only) and we have booked tickets for that price.
Surprisingly, we got the Invoice copy that shows the value of Rs.2, 27, 913.16 (in INR) with confirmed tickets to sons email ID.
Shockingly, Now Citi back further increased which shows in the bill, purchase value as : Rs.2, 37, 227.31 (in INR). Rs.28, 803.92 charged extra. which needs to be returned by Citi Credit card department.
As CITI back has taken huge margin in-between which is not acceptable.
Complaint by: Murali Krishna Cherukuri for Lohit Venkata Sai (my son)