Camila Cabello Reveals She's Suffering From Dehydration, Cancels Performance on Taylor Swift's Tour

Camila Cabello is canceling a performance on Taylor Swift‘s Reputation Stadium Tour after falling ill.

The “Havana” singer, 21, told her fans Monday night on Twitter that she was canceling her performance in Seattle, Washington after she went to the hospital following her performance on Sunday night’s 2018 Billboard Music Awards.

“So yesterday after my performance at the billboards, I was feeling really sick and ended up in the hospital to get checked out,” Cabello tweeted.

“They ran a lot of tests and everything is fine, but the diagnosis was basically dehydration and I also have a low grade fever — the doctors have told me I really have to get rest otherwise I won’t get better — so unfortunately I won’t be able to perform my set during the Reputation tour in Seattle tomorrow.”

“I’m so sorry to let you guys down and I promise I will make it up as soon as I can! I guess sometimes I just push myself too hard and I promise I’m gonna take better care of myself,” Cabello continued.

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She added, “But anyways!!! Last night I realized I didn’t have time to say thank you for my award, thank you for caring about me, thank you for sticking by me, it’s officially been a year since we started this journey together, and here’s to more memories, more joy, more love, more music, more health, and more life!! I love youuuu.”

RELATED: Camila Cabello & Normani Kordei Reunite for the First Time in 2 Years Since Fifth Harmony Split

Cabello reunited with her former Fifth Harmony member Normani Kordei at the award show in Las Vegas. The pair posed together for the first time in two years since news broke Cabello had left the girl group in December 2016.

Both performed during the show with Cabello taking the stage alongside Pharrell Williams to sing “Sangria Wine” and her hit “Havana” before picking up the award for chart achievement.

In March, Cabello opened up about touring with Swift comparing the tour to a “big slumber party.”

RELATED VIDEO: Taylor Swift Kicks Off Her Reputation Stadium Tour with Lots and Lots of Snakes (and Joe Alwyn!) — All the Details

“For me, it’s a dream come true. When I first met her four years ago, I was like, ‘I really love you,’” she told Entertainment Tonight on the carpet of the iHeartRadio Music Awards. The pair originally met at the MTV Video Music Awards years before. “I was like, ‘Man, I really look up to you. You really inspire me.’ She was one of the people that made me wanna start songwriting, so it’s really amazing.”

Add Charli XCX, the one-woman British hit-making factory, into the mix and fun is bound to happen. “I’m, like, really looking forward to the tour hangs, you know? It’s going to be like a big slumber party.”