Another United Airlines debacle left a Hawaii mother holding her 2-year-old son in her lap for a more than three hour flight, despite paying nearly $1,000 for his seat.

Last week’s incident came after the airline sold her son’s seat to a standby passenger on the last leg of their trip from Honolulu to Boston.

"We had both our tickets scanned, we both went on board no problem," Shirley Yamauchi, told Hawaii TV station KITV. Then a man approached them and showed he had the same seat number, 24A, as the boy.

"It was very shocking. I was confused. I told him, 'I bought both of these seats.'" The flight attendant came by, shrugs and says 'flight’s full,'" Yamauchi said.

Yamauchi, 42, told the station she didn't want to cause a scene, remembering recent United incidents such as the Kentucky doctor, David Dao, who was violently dragged off his flight in April.

"I'm scared. I'm worried. I'm traveling with an infant. I didn't want to get hurt. I didn't want either of us to get hurt," she said.

Instead, she sat with her son Taizo on her lap — or with him standing between her legs — for the entire flight. "I had him in all these contorted sleeping positions,” she told KITV. “In the end, very sadly, he was standing up between my knees."

Guidelines on the FAA’s website strongly advise against a child sitting on someone's lap: "Your arms aren't capable of holding your child securely, especially during unexpected turbulence."

"What happened to my son was unsafe, uncomfortable and unfair," Yamauchi said.

United Airlines said the seat-reselling error occurred after agents inaccurately scanned the boarding pass for Yamauchi’s son. “As a result, her son’s seat appeared to be not checked in, and staff released his seat to another customer," the airline said in a statement.

The airline apologized for the incident and told USA TODAY it refunded Yamauchi’s tickets and provided additional compensation.

Yamauchi told NBC she is unsatisfied with the explanation. “I saw them zap both tickets. There was no issue, no problem. They let us through. It just doesn’t add up,” she said.

She also doesn’t agree with the compensation: “It doesn’t seem right or enough for pain and discomfort.”

Yamauchi said having to hold her son was an ordeal. "He's 25 pounds. He's half my height,” she told HawaiiNewsNow.com. “I was very uncomfortable. My hand, my left arm was smashed up against the wall. I lost feeling in my legs and left arm."

The teacher told the website she bought the tickets in March to go to an education conference. Because the airline requires children over the age of 2 to occupy their own seat, she purchased a ticket for her son, paying almost $1,000 for each one.