This is a dupe and was discussed before: https://news.ycombinator.com/item?id=2915374
The headline is deceptive enough that I would characterize it as a lie. Apparently she was indeed rescued "after" using some gimmicky signal trending on TikTok, but not because of it. "The guy that called the police have said in interviews that he didn't understand the hand sign nor understood it as a hand sign. He reacted because she looked distressed. Empathy and attentiveness saved the day, not some 'tiktok' trick", as tokai noted in the previous discussion. [1]