Celebrities really need to be on the lookout for people pretending to be Greta Thunberg.

In a new Instagram video while self-isolation, singer Troye Sivan shared the story of how he got catfished by a fake Greta Thunberg.

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The 24-year-old explained that his manager had received a call from someone claiming to be Thunberg’s dad, and that they were putting together a project called “Stars Save the Earth”, which already had Leonardo DiCaprio and Prince Harry attached.

“I was like, ‘Oh my God, this girl is so inspiring, and now she wants to work with me.’ That’s crazy,” Sivan said.

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He got the fake Thunberg’s number and exchanged some texts with her before realizing that he was being pranked.

Sivan finally put everything together when he saw headlines several weeks ago about Prince Harry being fooled by the same Russian hackers.