Free Traffic Legal Advice

Hi,
PCN received for not paying toll on Mersey Gateway Bridge Nbound on 27th March.
I did cross the bridge as detailed, however I also paid the toll afterwards.
I can't find any email receipt for the payment to confirm that I entered VRM correctly, but the payment is shown on my bank statement (for the following day: I paid on the day but I crossed but processed the next day).
I can easily believe that I may have typed something wrong, but I think it's unlikely (although possible) that I typed my VRM wrongly, didn't notice that the wrong vehicle type was listed, and also typed my email address wrongly.
I have an ARN number for the payment from my bank.
If I attempt to make representations on the merseyflow website, I get the message 'PCN not valid' see screenshot. Does anyone know if it takes a few days to be able to access on the website?
Does anybody have any advice on how to proceed?

Many thanks for taking the time to read!!

How bizarre! You are quite right I'm seeing the same.

I rang them but they don't have much idea. They have asked me to send an email with details and the ARN and they will look into it.

I will do that and give them a few days. Presumably the important thing is to make sure I get confirmation the PCN confirmed as cancelled or else make representation by post within the 28 days.

Thanks for looking!