Charged double for parking. All visitors to ORTIA please beware!!

I recently booked parking at ACSA Parking Online, as it seemed to be cheaper to book in advance at the long term parking. I booked for 4 days and paid R324 in advance, only to be charged R420 AGAIN when I left the parking area. You have to use the same Credit Card from which the booking was made. So I ended up paying R744. Customer services refuse to assist or even answer my desperate attempts to have the matter rectified. It's nothing other than *****.