PPS pay & display

[Elsiemary]

My husband helped someone working pn an adjacent building site to the car park. The employees van was on for repair. Husband followed sat nav onto pay & display, too busy concentrating on site to notice sign. Waited in car (not parking bay)for site worker to arrive with tools. After 17 minutes drove out onto highway. Received letter from PPS with £60 fine. Wrote to them explaining was not taking up parking space, not obstructing anyone, just waiting for person to come out of site office carrying tools, & had no intention defrauding PPS, with map marked showing where car waited near site office. Appeal rejected, fine paid to avoid extra added. Can we appeal to Parking Organisation if which PPS is mrmber?