One day after Muhammad Ali Jr. spoke with members of Congress about being detained at a Florida airport last month, he was briefly stopped again before boarding a flight on Friday afternoon, his lawyer said.

When Mr. Ali, whose father died last year, arrived at Reagan National Airport in Washington on Friday for a flight to Fort Lauderdale, Fla., he gave his Illinois identification card to a JetBlue agent to get his boarding pass, said his lawyer, Chris Mancini, who was traveling with him and witnessed the episode. Almost immediately, Mr. Ali was told that there was a problem and that the agent needed to call the Department of Homeland Security, Mr. Mancini said.

Mr. Ali, 44, was asked his date of birth, where he was born and his Social Security number, Mr. Mancini said. After answering the questions, he was told that his Illinois-issued identification card, which expires in 2019 but is not a driver’s license, was invalid for flying.

“The same state ID from Illinois that he traveled to Washington on was rejected,” Mr. Mancini said in an interview on Friday night. Mr. Ali then produced his United States passport, which was accepted, and went through security and boarded the flight with his mother, Khalilah Camacho-Ali, the second wife of Muhammad Ali, and Mr. Mancini.