Visa DMS Link

There’s this thing called “visa DMS link” that charged me R1000. When I phoned fnb they told me that if a merchant does not have fnb approved checkpoint then I will be charged with this. I payed at a flea market and swiped for about R1000. So now with this new thing I pay double the amount for something??? This is outrageous! Plus if I withdraw cash to use at places I still get charged with bank charges for withdrawing ???