Demi Lovato is calling in sick.
The "Sorry Not Sorry" singer was forced to cancel her concert at London’s O2 arena after falling ill.
"I write this through tears of frustration and sadness that I have to postpone my concert tonight due to being very, very sick and with swollen vocal cords," she wrote.
Lovato continued, "If I go on tonight and injure my vocal cords any more I could potentially have to cancel the rest of the tour. I’m so, so sorry to disappoint any of my fans in London that have traveled hours to be here by plane or car and to all of the fans that got these tickets for a special occasion."
Lovato has tour dates scheduled this week for Tuesday, Wednesday and Friday — no word yet on whether or not those dates will need to be canceled as well.