If you insert a different credit card to the one used to make the online booking the system will process this as a separate transaction. You will be allowed to enter the car park. However, at the exit barrier the second card will be charged the parking fee based on the then current drive up fee. Your pre-booked transaction will be treated as a ‘no-show’ and your pre-booking may still be charged to your card account. It is important therefore that you bring the same card used to make the booking.