When Sanjay Dhir parked near the Mailbox in Birmingham on a Sunday afternoon in March last year, he thought he had done so legally.

Moments later, a parking ticket had been slapped on his windscreen.

The 34-year-old safety consultant from Coventry insisted there had been no signs telling him he could not park in the spot and he appealed to Birmingham City Council. The council refused his appeal on a number of occasions, but eventually sent a letter saying it had decided to let him off.

Mr Dhir said: "Back in March 2006, I got a parking ticket on a Sunday afternoon by the Mailbox after having lunch with a friend.

"I had parked on a single yellow line with no sign. I appealed and got the usual standard letter that said I was in the wrong and still had to pay #60, so I appealed a couple of times.

"It went to the National Parking Adjudication Service (NPAS) and then I got a letter from the council, which said it had been cancelled.

"But I then received a letter from NPAS, which stated that the parking ticket issued to me was not compliant with the Road Traffic Act 1991." According to NPAS, Mr Dhir’s ticket should have featured two dates – the date of contravention and the date of issue.

But the ticket only featured one date and was therefore invalid.

The letter referred to a High Court ruling on a case in Barnet, London, last October where a motorist, Hugh Moses, had appealed against his parking ticket, on the similar grounds that it did not feature two dates.

According to the Barnet case, anyone who has ever received a parking ticket with only one date on it has been issued with a ticket they do not need to pay.

Barrie Segal, who represented Mr Moses and is responsible for www.appealnow.com – a website to help motorists – said he had been contacted by Mr Dhir shortly after receiving the ticket.

He said: "The real problem is most motorists say they cannot be bothered, or are intimidated by the council or feel they cannot go up against them, but they can.

"If the same thing happens to them, they should certainly appeal and simply quote the Barnet v Moses case and the council should immediately cancel that ticket. If the council does not listen, they will be acting in a criminal way."

NPAS said money could not be claimed back as local authorities were not aware of their mistake.

But Mr Segal said: "In respect to tickets that have already been paid, I believe the council must refund these tickets.

"This has been an issue for a long time. My suggestion to people who have received a ticket with one date, is to write to the council and say, 'I have paid this ticket and I shouldn't have.

"I am giving you 14 days to pay me if. If you do not, I will issue a small claims court writ' and go from there."