This means that only the driver (the hero) knows that Tang Wei (the heroine) is a mistress and why she went to the United States to give birth. Before that, Tang Wei (heroine) only thought that only the driver (hero) knew that Tang Wei's boyfriend had an accident, and Tang Wei became penniless.

Hongmei Mai means that after answering this phone call, she knows all the secrets of Tang Wei. It is estimated that Tang Wei's boyfriend's wife told Hongmei Mai that Tang Wei was a mistress or something and her husband was arrested. Anyway, Hongmei Mai can guess that Tang Wei is a mistress, and now he has no money. )

In the past, Tang Wei was a woman who worshipped money. She was very bossy. Hongmei Mai told her that she answered the phone and that she could contact her when she returned to China. This well reflects the change of Tang Wei's role, becoming mature and no longer bossy (which may explain why Hongmei Mai is willing to help her).