Demi Lovato Steps in for Selena Gomez as a Headliner at 2016 Global Citizen Festival

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Demi Lovato has a huge new gig coming up.

The 24-year-old singer announced on Wednesday that she'll be performing at the 2016 Global Citizen Festival on Sept. 24 in New York City's Central Park, where she'll be joined by Rihanna, Kendrick Lamar, Major Lazer and Metallica. Lovato's addition to the festival comes after Selena Gomez was originally set to perform, but Gomez has since canceled due to health issues. Last month, the "Hands to Myself" singer announced she's taking a break to deal with anxiety, depression and panic attacks caused by her ongoing battle with lupus.

The Global Citizen Festival is an action-rewarded, awareness-driven free music festival where fans engage with causes in order to win tickets. Lovato, an outspoken advocate for mental health, talked about the A-list event's importance in a statement.

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"The Global Citizen Festival combines music and activism in a way that inspires and affects millions around the world," Lovato said. "I am proud to support this amazing organization’s ongoing efforts to improve global healthcare and to end extreme poverty."

Other celebs at the annual event will include Olivia Wilde, Forest Whitaker, Chris Rock, Dianna Agron, Malin Akerman, La La Anthony, Connie Britton, Andy Cohen, Taryn Manning, Bill Nye, Aaron Paul, Kal Penn, Pete Wentz, and Bonnie Wright. Usher, Chris Martin, and Ellie Goulding are also set to perform.

Fans can win tickets to the festival by first registering on in order to start earning points through taking action to end extreme poverty. Actions can include signing petitions, sending tweets, sharing information on their social media channels about issues affecting the world's poor, sending emails to world leaders, and more.

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In addition to the Global Citizen Festival, Gomez, 24, has canceled gigs for the remainder of the year. A source close to the former Disney star told ET that the break came after Gomez said she "hadn't felt like herself" lately, and that it is "absolutely not related to alcohol or substance abuse."

"She decided to clear her calendar for the year in order to have this be her priority for future happiness and didn't want to leave any promoters at bay," the source said. "She feels relieved that she can now make more sense of why she was feeling the way she was and is optimistic about the future."

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