Twinkle, twinkle, twinkle Why can't I go back?

Lin Beixing went back to the past by deleting the text messages on her old high school mobile phone. Without deleted messages, Lin Beixing could not go back in time.

When "Twinkle, Twinkle, Bright Stars" started, Lin Beixing broke up with her boyfriend Yu Zhan who had been in love for many years. She was bored at home and dug out her old cell phone from high school. She accidentally deleted the text message on her mobile phone and then traveled back to the past through time and space. After that, Lin Beixing needs to delete the text messages on the old mobile phone before crossing every time. At first, Lin Beixing completed the crossing by deleting the SMS of the old mobile phone. Later, the message was deleted and could not be crossed. Lin Beixing is very sad. Later, Lin Beixing and Wheat reunited. Wheat gave Zhang Wansen's old mobile phone in high school to Lin Beixing, and Lin Beixing found the confession message sent to Zhang Wansen on his mobile phone that year. By deleting the confession message on Zhang Wansen's mobile phone, Lin Beixing completed the last crossing, successfully saved Zhang Wansen and finally returned to his own world. The text messages of both mobile phones are gone, so Lin Beixing can't travel back through time and space.