It's not quite right - a key distinction is that they didn't use the not having a valid ticket contravention but used not paying - you didn't have a valid ticket.
It's also an informal challenge at this stage.
Do you have an evidence your wife was less than an hour - belt and braces.
See what others say but I think the below will do.
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I am writing to challenge the Penalty Charge Notice as the contravention of not paying the parking charge did not occur. No charge is due in the first hour and the car was parked for less than an hour.
The penalty was issued because my wife, who had borrowed my vehicle for the day to take our son to the hospital, accidentally selected the wrong vehicle registration when booking parking through the RingGo app. She had meant to select VO23 UCC (the vehicle she was using), but the app defaulted to LR13 ASV (her own car). As a result, although a parking session was booked, it was linked to the incorrect vehicle registration.
I have attached the RingGo receipt as evidence for the free 1 hour session.
I note the recent reviewed decision at London Tribunals, case 2220912034 (Decision Date: 22 Jan 2025). The adjudicator ruled that if a parking charge is not due, then the contravention “parked without payment of the parking charge” could not have occurred given parking was less than 1 hour. He also said your conditions of use explain to the motorist that a ticket or Ringo session is to be obtained at the time of parking. They do not say that a parking charge is due for the first hour if that condition is not complied with.
Given the charge was not due, and noting that my wife made an honest mistake with booking the session, I respectfully request that this PCN be cancelled. Please confirm in writing that my appeal has been accepted.
Yours sincerely,