Rob Rausch and Andrea Carmona left each other on bad terms — to say the least — on “Love Island USA” … and all eyes were on them when they were seen together for the first time since the Season 6 reunion.

A source familiar with the situation tells TMZ … Andrea and Rob unwittingly both showed up to a Celsius event in Miami not knowing the other would be there. While this meeting could’ve gone either way … we’re told the two got along just fine.

Check out the pic … they were even snapped enjoying a cold plunge together!

Fans will recall Rob initially dumped Leah to be with Andrea … and fell so hard he promised to follow her off the show when she got kicked off the island early on in the season. Rob ultimately didn’t follow through on his promise, staying on the island and hooking up with other girls.

Afterwards, Andrea posted an avalanche of content on her socials dishing on the experience in a way that Rob found so distasteful, he decided it was best not to even consider rekindling what they had.

But make no mistake, Rob told Alex Cooper he still thinks she’s a good person when he stopped by her popular “Call Her Daddy” podcast.

He said, “When she left, she was in a position where she could’ve said a lot of mean things … All she said was how much she cared about me and then left. I thought that was so good.”

Our source called the show a “bonding experience” for the two of them because of the vulnerable position it put them both in.

“Seeing Rob was a total surprise, but a happy one,” our source said. “She felt it was a full-circle moment.”

They definitely had a good time … in addition to the cold plunge, they also posted a TikTok with Kendall and Nic on a yacht.