Warnings of unfair fines have circulated after cameras in St Albans failed to register when drivers left a car park, and gave them a £50 penalty.

A taxi driver in St Albans, Ali Chowdhury, escaped a £50 fine which was issued by ParkingEye for being in Morrisons car park on Hatfield Road for 19 hours from January 27 to 28.

He knew his car had not been parked there for so long and appealed the fine - Ali has only just got a letter this week to let him off.

Something had gone wrong with the technology which monitors the car park, he believes.

Before Ali knew it had been rescinded, he said: “I understand that there are some people who do park their cars there for a long time, but I feel like I’m being scammed and I am not going to let it go.”

The taxi driver is now worried about vulnerable people who have a weak memory, or who are not strong willed, and who may just pay a fine - he wants people to know his story to encourage them to appeal if it is undeserved.

He said: “I cannot be the first person this has happened to, and God knows many people have paid it and it will keep going on and on.

“It seems very wrong and it’s good to make people aware.”

A hairdresser and nanny from Harpenden, Rachel Clark, had a similar experience in 2015 when she was fined £50 for being in the same car park too long – she had in fact been there twice in one day.

Rachel paid the fine quickly because after two weeks the penalty charge rises, and at the time she could not afford to lose the appeal.

But with picture evidence the fine should not stand, ParkingEye promised Rachel a refund, she says – the cash has still not been returned to her, two years later.

She said it was “stressful”, she is still “not over it” and is pursuing the claim.

Adding: “I paid it because I didn’t want it to be hard in the long run, but I think it’s very unfair to be honest.

“I would like to trust that they will go, ‘fair enough, here you go, here’s your money back’, but I am also at the stage that it’s taken this long, can I be bothered to keep doing this?”

A radiographer who lives in St Albans, Elizabeth Cooper, says she was hit with the fine in from Morrisons car park around Christmas-time last year for parking overnight, when in fact she had parked on consecutive days.

The fine was quashed after she went into Morrisons customer service desk and the people behind the counter helped her.

She says: “Some people will just pay to save the hassle or being fined again, and it was a waste of time.

“What concerns me is someone else would have paid the fine and it’s just the fact that there’s clearly a problem with the system because it’s not detecting cars coming in and out – I think it happens quite often.”

At the Royal Free Hospital, where she works, Elizabeth said the same systems control the car park – she says there was a “vulnerable patient” who came in with 12 fines because he had come to and from hospital day after day for his treatment.

A spokesperson from ParkingEye: “We encourage people who have received a parking charge to appeal if they think there are mitigating circumstances, and instructions about how to do this are detailed on all communications and on our website.”