The back-and-forth all started when Austin posted a cute selfie to showcase his freshly-done hairstyle.
Amidst the many comments Austin received praising his new style, Justin jumped in and commented on the pic himself, sarcastically calling out the singer for copying his look.
When Austin saw Justin's comment, he responded with a comparison of his own! He posted a side-by-side pic of both guys and wrote "@justinbieber lol it's all good bro. Your new look kind of looks like my old one though."
It turns out the guys aren't really fighting with one another, they're just having some fun, and Justin's hilarious follow-up comment proves it.
Do you think Austin is copying Justin's hair? Do you think his response was great? Let us know your thoughts about the situation in the comments section below.