I bought a car for £3,799 two days before Christmas from Cargiant, which claims to be the world’s largest used-car dealership.

After driving it for three days I realised that the front number plate differed by two digits from the rear one. This put me at risk of a fine. Due to the Christmas holiday Cargiant said that a manager would not be available for three more days but, in the meantime, the company would pay any penalties I might receive by entering car parks that have vehicle registration recognition.

They also offered to cover the cost of a hire car, but as it was by then Boxing Day it was impossible to find a local company that was open.

Human error was blamed, in which case many humans erred, for the car had passed its MOT and had supposedly undergone rigorous checks by Cargiant staff. I therefore had to cancel my travel plans over the Christmas period, but Cargiant has made no attempt to offer me any sort of refund or compensation. LB, London

Incompatible number plates should have caused the car to fail its MOT and it’s extraordinary that this discrepancy went unnoticed by so many. As you say, it’s illegal to drive a car with incorrect number plates and you could have been liable for a £1,000 fine if caught by police. Cargiant, when I contact them, offers apologies and claims it was willing to meet all your demands from the outset but was waiting to hear from you. You say this is untrue and that you were told that as you had incurred no direct expenses you were not due a payout. What they have now done, galvanised by media attention, is correct the number plates and commission another MOT. They say they will compensate you for the stress and inconvenience if you specify a sum. You might wish to take advice on what amount would be reasonable.

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