Bella Thorne got into a heated Twitter exchange with her ex Tana Mongeau after accusing her of breaking "girl code."

The former Disney Channel star and YouTube personality engaged in a public argument on Wednesday night (July 18), which all started after Thorne tweet that she and Mongeau were no longer "good." The pair, who dated for a little over a year, split up in February, however, they seemed to be on great terms... until now.

“Tana and I are no longer good. She broke girl code I’m over it," Thorne declared.

Though the actress didn't go into detail about what sparked her fury, their Twitter exchange went down one day after Mongeau was spotted out with Thorne's ex-boyfriend Mod Sun. The pair were seen leaving a restaurant in Hollywood together this week. Plus, it might explain what Thorne means when she claims Mongeau "broke girl code."

However, the Mongeau definitely seemed confused and unaware of why Throne is so upset, replying, “????? imagine taking every time ur mad at me to twitter but then telling ppl how much u care about me……………….. wtf is this b."

The Shake It Up star then retweeted her former flame's message, writing, “U legit started dating me for twitter.. how about u answer ur phone and talk to me instead of being on Twitter.”

“Dude what are you doing Bella? Like I have no idea why you’re mad, I’ve been texting you every minute since you tweeted, and for you to be tweeting me something as hurtful as saying I dated you for Twitter is literally f---ing nuts & if you honestly think that damn I lost you," Tongeau fired back.

It's unclear what led to this surprising feud, but their exchange ended with Mongeau's tweet, leading fans to believe the two may have taken their argument offline. We'll have to wait for one of them to clear things up, but everything between them seemed fine. Last month, Thorne even wished Mongeau a happy birthday with a sweet tribute.

On that same day, Mongeau announced her engagement to fellow YouTuber Jake Paul. Thorne reacted to the news by posting a series of Instagram photos that show her crying. “When ur ex gets engaged," she wrote.