A passenger on a United Airlines flight from Houston to Washington, D.C., accused the airline of giving her first-class seat to Rep. Sheila Jackson Lee, D-Texas.

The congresswoman, in turn, said it appeared the passenger targeted her "because I was an African-American woman."

Jean-Marie Simon, 63, said she purchased her flight for the last leg of her trip from Guatemala to Washington on Dec. 3 with 140,000 airline miles, the Houston Chronicle reported Saturday. When she attempted to board her flight on Dec. 18, she was informed her seat had been sold, and she was given a $500 voucher and re-seated in Economy Plus.

After the flight was delayed, Simon said she saw Jackson Lee board with a flight attendant before the other passengers. She said she did not know who the congresswoman was until another passenger told her.

Simon went to the front of the plane and snapped a photo of the congresswoman in her reserved seat. Afterward, a flight attendant sat down next to her and asked if she "was going to be a problem" on the flight.

United said Simon's seat was given up after she canceled her flight through the United app.

"After thoroughly examining our electronic records, we found that upon receiving a notification that Flight 788 was delayed due to weather, the customer appears to have canceled her flight from Houston to Washington, D.C. within the United mobile app," United said in a statement. "As part of the normal pre-boarding process, gate agents began clearing standby and upgrade customers, including the first customer on the waitlist for an upgrade."

Simon denied canceling her flight and sent a screenshot to the Houston Chronicle of her United profile showing the flight as "inactive."

The airline responded saying that because she eventually took the flight, it would not say "canceled" next to it.

Jackson Lee issued a statement Saturday saying she "asked for nothing exceptional or out of the ordinary and received nothing exceptional or out of the ordinary."

"Since this was not any fault of mine, the way the individual continued to act appeared to be, upon reflection, because I was an African-American woman, seemingly an easy target along with the African-American flight attendant who was very, very nice," the congresswoman said.

Simon told the Chronicle the congresswoman was accusing her of racism and said she had no idea who was given her pre-booked seat when she originally complained at the gate.

She said she wants a written apology from the airline.

United came under fire earlier this year when a video of a passenger being forcibly dragged off a plane after he refused to give up his seat went viral.