Last week, it was reported that Justin Bieber was going to take part in the annual Thanksgiving Day Parade in New York City, but shortly before the singer was scheduled to shoot his parade performance on Tuesday, Nov. 24, the "Sorry" hitmaker canceled the appearance for unknown reasons. He also canceled his "Late Show with Stephen Colbert" appearance on the same night, and TMZ reports that sources said that the 21-year-old was dealing with "personal issues" but not related to drugs or alcohol.

Bieber took to Twitter on Tuesday to apologize to Colbert for his no-show.

"@StephenAtHome, thank you for the understanding as sometimes life kicks our [expletive] and we need to deal with it. I will see u soon. Thank you," he wrote.

Fans expressed their concern for the singer, but he appeared to be fine as he was spotted at a bar on Thanksgiving Day, according to E! News.

"He was playing arcade games and having a cheeseburger and drinking a few beers," said an eyewitness to E! Another insider said that the pop star even bought shots for several people inside the bar.

On Friday, the "What Do You Mean" singer made a surprise appearance at LA's Shrine Auditorium and performed three songs with The Chainsmokers. According to the Daily Mail, the crowd initially looked surprised, then delighted, by the band's guest star. Bieber took to his Instagram account to share a photo of him looking out at the crowd and captioned it, "Thank you to the Chainsmokers, u guys put on a [expletive] of a show and honored to be a part of it."

While the singer has yet to talk about the real reason why he cancelled his Thanksgiving appearances, a source told TMZ that Bieber has "been on a virtual roller coaster—with his moods swinging like a pendulum—and it's just become too much."