Deducting huge incorrect amounts for purchases abroad

On the 28 of June 2023 I filled up a car with fuel at DCB Eindhoven for €68.35, I would like to know how FNB deducted from my credit account number: ***38 6102 the amount of R2603.50? I have the receipt for €68.35 which is most definitely not R2603.50. If this is not rectify I will be referring this to the banking ombudsman.