Is it useful to call the police when the money tray is gone?

Useful. After the funds are cheated, calling the police is the main way to recover the funds. Once you find that you have been cheated, you should call the police in time, because since you have been cheated, it is likely to involve criminal violations. Only the police have the right to investigate ordinary criminal cases, and can take investigation measures and criminal compulsory measures to find out the flow of funds by means of inquiry, seizure and freezing, so as to recover funds and arrest the perpetrators. For other occupations or personnel, they have no power in this respect. If they believe the promise of others to recover without authorization, they may fall into a new scam. Therefore, when you can't recover funds through your own ability, you should choose to call the police decisively and promptly.