Spurious Charges for Use of Debit Card on their Site

Added a ********** charge of R 510 to my flight booking claiming it was for using my card on their site (card payment is a valid form of payment on their site).

Stayed on a call for close to 30 minutes speaking to some guy who asked me to hold several times so he could confirm from the manager. Call couldn't be transferred to manager cause he was in a meeting.