The most probable answer is that the e-mail address you are entering has not been provided or is linked to the mobile account you are attempting to access.
If you registered to Parkmobile by telephone, either recently or historically (you only need to have ever called us once in the past), then your e-mail address would not have been captured. If you did register by making payment by calling and it is your first time of logging in you should enter the mobile number you called from and the last four digits of the payment card used on the day.
