Upon returning to the UK in the early hours of 02/07/16 there was a system fault with the parking system which resulted in the computer system not recognising that I had pre paid for three vehicles parking. As there were several flights that had landed at the same time this resulted in a lengthy delay exiting the long stay car park as there were a number of vehicles stuck and only one member of parking staff to deal with the entire site. I had also upgraded my disabled parents to park in the short stay car park as they have restricted mobility which resulted in several paniced phone calls about not being able to exit the car park and them being told that they had to pay £157 to leave. I had to pay to park in the pick up and drop off point so that I could run to the parking office to sort it out as the member of staff was so busy he couldn't answer the intercom system. On the plus side the member of staff was very hrlpful given the number of people who weren't very happy with what had happened. Not what you want after a 5 hour flight with a 2 and 1 year old having paid in excess of £130 to park.