On Friday, the airline announced that Flight 3996 was diverted to Akron after officials discovered the animal was on the flight bound for St. Louis, airline spokeswoman Maggie Schmerin said. United said the dog was successfully reunited with its owner.
United told CNN the unidentified animal was "safely delivered to its owner".
The mix-up was the third incident involving a pet on a United Airlines flight in just a week.
According to United, compensation was offered to all passengers as a result of the diversion.
Swansea v Spurs confirmed XIs: Son leads the line in Kane's absence
But MK's academy were going to play Chelsea's academy at Stamford Bridge and they would not let me go as I had only trained once. But, and I don't understand why, there is still that feeling [to criticise him].
Kara Swindle and her two children took a United flight Tuesday from OR to Kansas City, Missouri, during a move to Wichita, Kansas.
Irgo arrived back with his family on Thursday after United chartered a private plane from Japan.
United Airlines is facing criticism after a dog died on a 3 1/2-hour flight and accidently shipping another dog to Japan.
In Irgo's place was a great dane that was supposed to be en route to Japan.
And the Harris County District Attorney's Office, in Texas, told a local news outlet that its animal-cruelty task force would conduct an investigation into the death. "I want to make sure that they actually do something to stop all of this and make sure that no one has to go through this".