Got a phone call from customer service, apparently they can't do anything as ParkingEye won't drop the charge. They asked if I received a discounted offer in the post and offered a £20 voucher to go towards paying it?
Apparently they think that paying £25 is a sweet deal and the best they can do, so I said I will not be paying so much as a pound and will not visit thier stores again if that's the case