Gwen Stefani is missing her fourth show in row due to an unknown illness.
The "Hollaback Girl" singer announced on Twitter on Thursday that she would not be able to perform her Valentine's Day show in Las Vegas — this marked the fourth show in a row that she's canceled. All the canceled shows have been part of her "Just A Girl" Las Vegas residency.
"I am still under the weather & will not be able to perform my #JustAGirlVegas show tomorrow, Friday, February 14 at @ZapposTheater at @PHVegas," she tweeted on Thursday, adding that she was "so so sorry" and still planned to perform Feb. 15-22.
Fans were first alerted to Gwen's illness last week when she canceled a Feb. 7 concert in Vegas. A few days later she tweeted out a similar message, indicating she couldn't perform on Feb. 8.
"I am doing everything I can to get well & plan to be back on stage for my shows February 12 – 22," she tweeted at the time. "Thank u for all of the well wishes. Hope to see you back in Vegas soon."
On Feb. 11, she tweeted, "I am so sad to announce that I am still unwell & will not be able to perform my #JustAGirlVegas show tomorrow, Wednesday, February 12."
Ticket holders for any of the canceled concerts can seek refunds.
Gwen's nearly two-year Las Vegas residency show ends May 16.