I parked my car in a Borough of Newham car park and inserted £4 in mixed change into the ticket machine for payment for a three hour stay, when I went to display the ticket I noticed that the ticket expired after two hours and the machine had only accepted £3.90p, I returned to the machine and saw that a 10p had jammed, I went back to the car and found a £2 coin.

I inserted that into the machine and it must have dislodged the 10p as the printed ticket stated I had paid £2.10p, the tickets were sequentialy numbered but four minutes apart. I left the 2 tickets on the dash with a covering note to explain that I had in fact paid £6 instead of £4 for my intended three hour stay. When I returned to the car I found a PCN had been issued for Contravention code 82 'parked after the expiry of paid for time'.

I appealed the ticket but it has been rejected because I returned to the vehicle and displayed another pay and display ticket with the intention of prolonging the paid-for parking time, which according to the Newham website is contravention code 84. So my question is, should I pay the reduced £40 fine, or pursue the matter on the grounds of:

A) Faulty machine.
B) Wrong contravention code, as I had not expired the paid for time.
C) De Minimis, as there was only four minutes between the issued tickets, so I had not left the car park and returned later.