Talk about an unexpected feud.

Justin Bieber, who had maintained a low profile since marrying Hailey Baldwin over the summer, found himself at the center of a nasty feud with Nickelodeon star JoJo Siwa after she debuted her new rainbow car on Instagram. The BMW coup convertible featured a personalized rainbow wrap, put on the car at West Coast Customs.

"Burn it," Bieber commented on Siwa's Instagram post.

His comment prompted outrage from fans and Siwa's mother, Jessalyn, who suggested he "burn your own things." Siwa held her own, quipping back at Bieber's comment almost immediately.

"@JustinBieber that's not the best idea," Siwa replied.

After getting attacked on all fronts, Bieber realized the error of his ways. He took to Twitter to make things right, assuring Siwa and her angry fans that he meant no harm.

"@itsjojosiwa I have nothing against you it was the car and the colors I didn't like I really hope you didn't think it was malicious or mean spirited," he tweeted, prompting Siwa to reply, "It's all good bro! you can perform at my 16th birthday party and we'll call it good!"

No word on whether Bieber actually plans to perform during the party.

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