Gun control advocate David Hogg said that Republican Sen. Marco Rubio of Florida cancelled a meeting after getting “triggered” but he apologized after Rubio’s staff called him out publicly for lying.

Hogg tweeted about the canceled meeting on Thursday from his social media account.

“Rubio staff said I can’t meet with him or his staff because I ‘trigger’ him. I just wanna have a conversation,” Hogg tweeted out. “Please meet with me @marcorubio I just want to figure out how we can stop these things from happening. We have to end the continuous debate and find out what we can agree on.”

Rubio’s chief of staff Michael Needham excoriated Hogg and called him out.

“No one said such a thing. As for the meeting, you must be confused as we had a 2p meeting scheduled with you,” Needham tweeted. “However, since you are lying and clearly using this all for self-promotion, that meeting is now cancelled.”

“Also, the reporter doing a profile of you knows the meeting is real since she was emailing yesterday with our comms team about it,” Needham said in a second tweet.

“Don’t lie again — we have receipts,” he threatened.

Hogg apologized soon after.

“[A]n honest mistake, got our meetings confused in the flurry and my staff misinformed me. I apologize. We’d still love to meet with you and have an honest, respectful discussion,” read his tweet.

“Deleted the tweet bc it wasn’t true but attaching here for transparency,” he added.

Hogg has been a vocal advocate for gun control since the mass shooting at Marjory Stoneman Douglas High School while he was attending. More recently, he complained about how difficult regulation had made it for him to start a company, prompting many on the right to ridicule him for supporting Democrats who pass laws to increase regulations.

Here’s more about David Hogg’s mission for gun control:

David Hogg FINDS Conservatism by Mistake | @Chad Prather www.youtube.com