You are not appealing. You are complaining to them. Tell them you will report them to the BPA for a breach of their CoP at 21.5a which states:
Photographic evidence must not be used by you as the basis for issuing a parking charge unless:
a) at least one of the images captured includes a clear record of the vehicle’s VRM to which the parking charge is deemed to apply;
b) the images bear an accurate time and date stamp applied at the point the picture was taken;
c) the image(s) show, where appropriate, the pay and display tariff receipt as displayed or not being visible;
and
d) images generated by ANPR or CCTV have been subject to a manual quality control check, including the accuracy of the time-stamp and the risk of keying errors.
It is pretty obvious that (d) has not been complied with. Also, if they've not supplied evidential photos on the NtK, that is another breach. Whilst they may have some file photos, they should include an unaltered (cropped or distorted) photo of the vehicle, including a date/time stamp.
Have you checked the details of the vehicle you suspect the VRM is of on this site:
https://vehicleenquiry.service.gov.ukIs your vehicle and the one you suspect it is of, the same make, model and colour?