Ghost Surveillance

Everyone else transmigrates, but I became a ghost? The protagonist, Gu Ning, is an ordinary, frustrated full-time mother. She gets caught up in a supernatural car accident and, due to a mistake by the emissary of the underworld, becomes a ghost and transmigrates back to her high school days. Against her will, she becomes a "ghostly observer," helping her younger self, who is still a human girl, in all sorts of ways as she tries to change the life she believes she failed at...