So much for Barbie and Ken. Amanda Stanton‘s BFFs Emily and Haley Ferguson accused Robby Hayes of cheating on the blonde beauty after Bachelor in Paradise wrapped. And on the Sept. 11 finale, the twins called out Robby for fooling around with an unidentified woman while at a concert in Colorado.

“He did cheat on Amanda,” Emily said during the taping. “There were pictures coming out.” When host Chris Harrison asked Robby if that was true, he denied it, saying, “That’s false.” Haley proceeded to ask him, “What happened in Colorado then?”

After the finale aired, Robby posted a lengthy message to Twitter with the caption, “Twitter asked me what’s happening… Well let me explain…” In the post, he says, “I’ll never understand why there’s such a desperate need to present an ‘innocent persona’ and resort to allowing allegations that are blatantly untrue be said about me by ‘the twins’ while one sits back and ‘unknowingly’ watches these malicious attacks continue against me.” Read the rest in the tweet below:

Amanda responded by posting one of the incriminating photos to Twitter with the caption, “Look what you made me do.” And in a direct reply to Robby’s tweet, she wrote, “‘A desperate need to present an innocent persona.’ — the guy who denies cheating when there is photo proof #beamanalready.”

Amanda had previously confirmed that the two had broken up at an event on Sept 6. “Robby and I are not together,” she told Us Weekly. “I’m not really sure how Robby’s handled the situation.”

As for what went wrong in the relationship, Amanda told E! that they just weren’t the right match. “He never really treated me like his girlfriend, you know? He was still going out with his friends all the time, kind of going MIA for a few days. It was just a confusing situation. I don’t think that he did anything wrong, I just think that he’s not ready for a relationship.”

But it seems like that fateful night in Colorado played a very big role in their split, and Amanda finally spilled the tea in an interview with Entertainment Tonight. “Basically what happened was there was a night where he was out in Colorado, and he was supposed to come home that night, but he had missed his flight and his phone died and I didn’t hear from him for a whole day,” she explained. “And then the next day he had called me in the morning and he was like, ‘Sorry, my phone died.’ And later that day, a girl said he was at a Zac Brown Band concert and sent me photos of him looking like they were making out all over each other. He says that they were not, I wasn’t there. So, I don’t know. I can’t tell you.”

There may even be a receipt from that alleged hookup, and it was posted to Robby’s own Instagram account. Last month, he shared a seemingly innocent photo with a group of girls. When followers began to wonder why Amanda was missing, a fan of the reality dating competition solved the mystery. “I’m assuming she wasn’t there because he was busy making out with the girl next to him at the ZBB concert last night,” she commented under the photo before Robby deleted it from his social media account.

However, Amanda was able to like the comment before it was removed, seemingly confirming she knew Robby was unfaithful to her. Luckily for everyone, the interaction was screenshotted by Bachelor fan account @pacoismynickname, who captioned the image, “Got this receipt.”

Reality Steve also reached out to the Instagrammer who claims to have seen Robby making out with the mystery blonde at the Zac Brown Band concert in Denver, and she stands by what she wrote. “They were all over each other,” she said. “I’m honestly surprised no one else has come forward saying anything.” As for photo proof, she made sure Amanda got copies. “It’s up to her what she does with it, but I was just trying to do the right thing,” she added.

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