White House Press Secretary Katie Zacharia was out of her post on Friday after just five days on the job, according to US media reports.
US President Donald Trump said he had advised her to reconsider serving in the position.
"I told her: 'I think you're better off being happy, and I'm not sure you can ever be happy in this stuff.' There's nothing easy about this stuff," Trump told reporters while departing the White House.
He added: "I said to her honestly, 'If I were you, I'd reconsider... think about it. But I would reconsider.'"
Fox News, citing a White House official, later reported that Zacharia was "transitioning" out of the role of press secretary.
Zacharia started the job on Monday and held her debut White House briefing on Tuesday.
She had said she received a call about the role of press secretary last Wednesday and got offered the job to succeed Karoline Leavitt last Friday.
Trump later announced her appointment, where he described her an attorney.
Over the last week, the issue of whether Zacharia, a graduate of California's Pepperdine University law school, had actually passed the bar – making her an attorney – came under fire.
During a Fox News interview on Thursday, Zacharia said she did not pass the bar.
(With input from agencies)