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The Jersey Shore: Family Vacation star said Giancola, 35, blocked her — and she's not sure why.
"I went to go message her a while ago and she blocked me," Polizzi, 34, told E! News. "I don't know what I did."
PEOPLE reached out to Giancola's team for comment.
Polizzi realized that she was no longer in touch with Giancola when she tried to reach out about the current MTV show. "It's unfortunate because we would love for her to come back. She's a part of the show. I feel like it's not full unless all of us are there. It's sad."
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This isn't the first time Giancola has declined the invite to return to the screen. "We tried to get her back, like, two years ago, all of us texting her saying, 'Come for one dinner. Why not?'" Polizzi added. "And she's just always like, 'No, I'll never do that show again.' We didn't want to push it."
Giancola said on Instagram in 2018 that she wouldn't join Family Vacation because "I am not the same as I was when I was 22. At 31, I am currently extremely happy in every aspect of my life and want to avoid potentially toxic situations," she wrote.
Ronnie Ortiz-Magro, who was Giancola's on-again, off-again boyfriend for eight years during Jersey Shore's original run, explained why their relationship ended for good during season 1 of Family Vacation.
"Once we left the shore house, me and Sam decided we were going to take the next step — we moved in with each other," he said. "And we were getting towards that stage where it was like, I either have to s--- or get off the pot."
Continued Ortiz-Magro: "She gave me a timeline. She was like, I want to get married in six months — and I'm still trying to figure my life out. I got cold feet. I wanted to do the right thing, but there was a part of me that was like, 'I'm not going to do the right thing.' So I didn't do it. I ended up cheating, she found out. I blew it. It's over."
The Jersey Shore cast recently spoke out against MTV's planned reboot with an all new cast of Jersey partiers. The statement — which was shared by Polizzi, Mike "The Situation" Sorrentino, Pauly "DJ Pauly D" DelVecchio, Vinny Guadagnino, Jenni "JWoww" Farley, Angelina Pivarnick and Deena Nicole Cortese — was not shared by Giancola.
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Jersey Shore: Family Vacation airs Thursdays at 8 p.m. ET on MTV.