At the end of March we parked at Albert Street car park in Birmingham and paid £4 for a ticket – we have a newish car and couldn't remember the registration number.

As our grandchildren were screaming we put the ticket in the car window – not knowing that one needed to insert the registration number for the system to work.

We have now been charged £60, even though we left the car park well within the time allowed.

Perhaps you should look into the organisation behind this as I believe their instructions are not clear. No ticket should have been issued if the registration number was a necessity for the system to work.

I imagine many people are caught out by this. SM, near Royston, Herts

Car parking machines increasingly ask for the buyer to input their registration details to stop drivers passing partially used tickets on to new arrivals.

However, we can't see on what grounds the parking firm – the controversial Sheffied-based firm Vehicle Control Services – can pursue you as you paid the correct price, and no one has lost out financially.

Its number plate recognition system even noted your car's details upon entry and exit – as shown on the demands it sent you.

A spokesman for the VCS, which describes itself as a leading UK supplier of parking enforcement, says: "A contract was formed when SM decided to park in the private car park at Albert Street and, as such, he accepted the terms and conditions of parking set out on signage at the entrance to and around the car park.

We maintain that the parking charge notice was issued correctly. SM has been given the option to appeal to POPLA, the independent arbitration service."

We asked parking ticket guru Barrie Segal who runs the parking fightback website, Appealnow.com, and his advice was to throw it in the bin and not to even bother appealing.

If you get a ticket from this firm – which among other things enforces "no-drop" areas at UK airports – there is plenty of advice on the internet.

Those posting on Consumeractiongroup.co.uk have reported that VCS will send a solicitor's letter, but the threats have no grounds, they say.

The business appears to operate on the basis that many people will just pay up without fighting it. We'd be following Segal's advice, but do look out for a "letter before action" which may suggest they are going to pursue it more formally. If so, then have your day in court – it would be extraordinary for a judge to rule against you, considering the parking company has made no loss.

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