Ashlee Simpson's career was never quite the same after her infamous "Saturday Night Live" performance in 2004, but it taught her "the power of no."

Simpson, 39, appeared on the sketch show to promote her debut album, "Autobiography." She appeared to flawlessly perform her hit single "Pieces of Me." When she took the stage a second time to sing the title track, the "Pieces" vocals played over the speakers once again, revealing that Simpson lip-synced her entire first performance.

On Monday's episode of the "Broad Ideas With Rachel Bilson & Olivia Allen" podcast, the mom-of-three revealed she lost her voice before the show and had two vocal nodules "beating against each other."

Simpson initially declined to perform due to her vocal issues but claimed NBC asked her to still perform with a pre-recorded track. "My band has never practiced this, this is not going to go well,” she recalled thinking at the time. "I can’t do this."

The moment taught her "the power of no," Simpson said, adding that "it was a humbling moment for me" dealing with the backlash.

People said "awful, awful things" after the performance, she recalled. "(I had) to find, at a young age, that strength to be like, 'I am good at this and I will keep going, and I will keep fighting.'"

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Ultimately, Simpson didn't need to have surgery on her nodules thanks to a vocal coach who "saved my life," she said.

The "Pieces of Me" singer returned to the NBC sketch comedy the following year to redeem her previous performance and promote her second album, "I Am Me." However, Simspon said she "can't find it anywhere" on the internet.

"I’ve searched and searched for that performance," she said. "I was really nervous when I was on there and I can’t find it anywhere."

Both Simpson's first and second appearances on "SNL" are not available on the sketch comedy's official social media, although the first one has been widely shared on unofficial pages.

Simpson's last album, "Bittersweet World" was released in 2008, but it did not amount to the success of her first two. Her last single, "Bat for a Heart," came out in 2012.

She later returned to the music scene in 2018, joining her husband Evan Ross under the band name Ashlee + Evan. The pair went on a brief tour in support of their self-titled EP in 2019.

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