Usher wasn’t himself while performing last night at Berlin’s O2 World, postponed from the night before due to illness. Midway through his “OMG Tour” stop, Ursh stood at the microphone visibly dazed, spending the next few minutes meandering across the stage before plopping down on the steps. As his backing tracks played, some fans booed and encouraged him to “go home” while he held the mic, but didn’t sing.

“After consultation with doctors, he has been advised to reschedule the upcoming dates in order to get the rest he needs to ensure a complete recovery,” said a rep for the R&B superstar.

Usher apologized to his fans who may have been disappointed. “I deeply regret having to reschedule the shows. I am truly sorry for any inconvenience I have caused my fans,” he stated. “My fans are the best in the world and I am looking forward to getting better so that I can give them the show they deserve.”