Rep. Adam Kinzinger (R-Ill.) is “not convinced” that Mark Meadows, former President Donald Trump’s last White House chief of staff, has turned over all relevant material requested by the House select committee investigating the Jan. 6 Capitol attack.

During an appearance Sunday on CBS’s Face the Nation, Kinzinger said Meadows was submitting information to the committee, but “in an attempt to make Donald Trump happy, he stops cooperating. We gave him plenty of space to come back and resume that. He has not.” Meadows turned over thousands of documents and text messages, but Kinzinger is “not confident” that he “handed over everything at all.”

Last week, The Washington Post and CBS News obtained text messages between Meadows and Virginia “Ginni” Thomas, wife of Supreme Court Justice Clarence Thomas. The messages were among those provided to the Jan. 6 committee, the Post and CBS News said, and show that Ginni Thomas, a conservative activist, urged Meadows to try to overturn President Biden’s electoral win.

When asked about the text messages between Meadows and Ginni Thomas, Kinzinger said he was unable to confirm or deny whether they had been provided to the committee. He also would not reveal whether the panel intends to subpoena Thomas. Last week, people with knowledge of the matter told CBS News committee members do want to speak with her and if necessary, will issue a subpoena.