Republican U.S. Representative Madison Cawthorn mocked MSNBC after an email mix-up reportedly revealed that a producer on The Rachel Maddow Show was “worried” he might want to make an appearance.

A “senior” producer on the show accidentally copied a member of the North Carolina Republican’s team in an email that expressed concerns over reaching out to his office about a group’s attempt to invalidate his future candidacy for office, according to a Monday report from Fox News.

The producer, whose name was redacted in an image of the purported email, asked that a network colleague contact Cawthorn’s office instead to avoid any “risk” that the conservative congressman would request an appearance on progressive Maddow’s show.

“We don’t have a relationship with his office and between you and me are a little worried that if we did inquire he might ask to come on and explain,” the producer reportedly wrote. “I know that is HIGHLY doubtful, but don’t want to take that risk.”

The Maddow producer was apparently unaware that Cawthorn’s office had been copied in the email. An MSNBC colleague reportedly volunteered to contact the congressman’s office instead of the producer.

Cawthorn quickly shared a link to the Fox News report on Twitter alongside the comment “Whoopsies ⁦@MSNBC!” He also retweeted multiple comments on the alleged email after lashing out at the attempt to “silence” him in a statement to Fox News.

“Fake news MSNBC doesn’t want to ‘take the risk’ that I’ll come on their show and trigger the left with my America First message and burst their woke dystopian bubble,” Cawthorn told Fox. “The left doesn’t want debate from conservatives, they want silence. And now we have it in writing. Sad!”

MSNBC was discussing contacting the first-term congressman about a group of 11 North Carolina voters who had filed a challenge with the North Carolina Board of Elections that could legally bar Cawthorn from running to represent the state’s newly created 13th Congressional District in the November midterms.

The challenge was filed on the basis that Cawthorn, a supporter of former President Donald Trump‘s false claims of massive election fraud in 2020, was ineligible due to a constitutional amendment banning anyone “engaged in insurrection or rebellion” from seeking office. The group noted that Cawthorn spoke at the Washington, D.C., rally that immediately preceded the Capitol attack.

The group Free Speech for People is backing the challenge. Ron Fein, the group’s legal director, told the Associated Press that the effort highlighted “the importance of defending the bedrock constitutional principle that oath breakers who engage in insurrection cannot be trusted in future office is essential to maintain.”

Luke Ball, Cawthorn’s communications director, said that the challengers were “comically misinterpreting and twisting the 14th Amendment for political gain.” Cawthorn himself also lashed out at the challenge, tweeting that the “woke mob won’t stop me,” while sharing a related article from a right-wing news outlet.