Canada

Go Public has learned of five other people that Air Canada also incorrectly deemed "no-shows" on three other trips, cancelling their return tickets and refusing to accept evidence such as boarding passes — even selfies taken on the planes — they hadn't missed an earlier flight.

The cases are cause for concern, since airlines need to know exactly how many people are on the plane and who they are, says an expert on methods of boarding passengers onto planes.

"If it is a systemic problem, like their computer systems not talking to each other, they should get it fixed," said John Milne, an associate professor of engineering and management at Clarkson University in Potsdam, N.Y.

"In the meantime, how can you ... cancel people's return flights when you know your records aren't reliable?"