A man from Denver was rebooking a flight for a family vacation when the purchase actually went through for a scammer.

The airline confirmed on Friday that the agent transferred a customer to an external number without using internal tools to validate it.

A Denver man is lamenting the loss of thousands of dollars after rebooking a United Airlines flight following the cancellation of an earlier one, according to a 9News report.

United Airlines has grounded flights nationwide on Wednesday night due to an issue with its weight and balance computer system.

United Airlines projects a record-breaking Labor Day weekend, expecting to carry around 3.1 million passengers from August 28 to September 2, a 220,000 increase from last year.

The airline’s travel alert page notes that a technology disruption may impact flights to or from 14 airports including Newark, Washington, Los Angeles and Chicago.

A United Airlines flight was allegedly delayed for four hours after a passenger smoked cannabis in the plane 's toilets. Flight UA1679 was due to take off from San Francisco airport to Cancun in Mexico on 5 August, but was delayed at first due to administrative issues.