There was no mistaking their car – the registration plates proved it was theirs. But it was bearing magnetic signs for the shuttle service and being driven by a stranger to drive people to and from Düsseldorf airport.
The family called the police, who confirmed on Thursday that the car had been left with a parking service – which also operated a shuttle service. And, Die Welt newspaper reported on Friday, the 21-year-old driver had neither a driving nor a chauffeur's license.
The company initially said the incident was a one-off mistake by a temporary worker – but then the family checked the milometer in the car – which showed it had been driven 400 kilometres while they were away.
The police are now investigating the matter.