Deepfakes create videos of people by modifying their faces or bodies using artificial intelligence (AI).
This week, a TikTok video claiming to be MrBeast offered consumers new iPhones for $2 (£1.65).
Meanwhile, BBC performers Matthew Amroliwala and Sally Bundock’s likenesses were used to promote a well-known swindle.
The Facebook video showed the journalists “introducing” Elon Musk, the billionaire owner of X, previously Twitter, who was allegedly pitching an investment opportunity.
Similar historical films purport to show him handing out money and bitcoin.
The BBC has contacted Meta, the owner of Facebook, which has yet to remove the post.
Instead, the videos are blocked by a graphic notifying potential viewers that they contain misleading material, as verified by independent fact-checkers FullFact, which originally reported the problem.
Meanwhile, a TikTok spokeswoman stated that the MrBeast commercial was withdrawn after a few hours of being submitted, and the account that posted it was terminated for breaching the company’s regulations.