The device – which was deemed safe by Samsung – is alleged to have set alight after overheating, leading to a Southwest Airlines flight having to be evacuated before take-off yesterday (October 5).
The carrier confirmed the evacuation of the aircraft, which had been due to fly from Louisville to Baltimore.
The Note 7 was recalled by the technology firm last month but Samsung said the problem had been identified and fixed, BBC News reports.
Samsung said it had launched an investigation into the new incident.
A Southwest Airlines spokesperson told BBC News: "A customer reported smoke emitting from an electronic device. All customers and crew deplaned safely via the main cabin door."
"We are working with the authorities and Southwest now to recover the device and confirm the cause," Samsung said in a statement. "Once we have examined the device we will have more information to share.”
The owner of the phone, Brian Green, told The Verge website, he had bought the device on September 21.
He explained how there had been a black square symbol on the phone’s packaging – used by Samsung to distinguish old or unsafe devices from replacement models.
Green described how his device was powered down, and had not been charging, when it began to overheat in his pocket onboard the aircraft.
After he threw it on to the floor of the plane, it started to emit a "thick grey-green angry smoke", The Verge reports.
The US Federal Aviation Administration (FAA) had previously issued a warning to airline passengers saying Note 7 devices should be powered down and not charged while on planes.
It has also advised against packing the phone into hold luggage.
The FAA is yet to comment on whether additional restrictions will be enforced after this latest issue.