Interested in United Airlines? Last year, the airline, one of the largest in the world, carried about a quarter of the total number of animals transported by air in the United States, but it was responsible for 18 of the 25, or more than 70 percent, of flight-related pet deaths last year, according to Transportation Department data.
It was carrying 33 passengers from Newark, New Jersey, to St. Louis, but the pet was due to fly from New Jersey to Akron.
The animal was mistakenly boarded onto the plane instead of a flight to Akron, Ohio.
Passengers were provided compensation for the delay.
Maggie Schmerin, a United Airlines spokeswoman, told CNN the dog had been "loaded onto the flight in error" and was now "safely with its owner". They are yet to come forward to identify themself.
United Airlines provoked worldwide outrage after a 10-month-old French bulldog died on one of its U.S. flights last week.
Kokito, pictured in an undated handout photo, died on a United Airlines flight on March 12, 2018, after being placed in an overhead bin.
"We chose the fastest option to reunite the dog with his family", said United spokesman Jonathan Guerin.
The dog was flown back to her on a plane after landing in Japan.
The airline faced fierce backlash and massive criticism when a customer on Monday reported a flight attendant told her to store her 10-month-old French bulldog, Kokito, in the overhead compartment for the duration of her flight.
On Tuesday, two other dogs belonging to other passengers ended up on the wrong side of the world in a colossal mix-up.
When his owners in Wichita went to collect him, they were greeted instead by Lincoln, a Great Dane whose family live in Japan and were on their way there without him.
Lincoln was forced to slum it in the hold of an ordinary flight.