What does it mean to send a message today saying that you owe money to the US Mission?

This is a scam. There is a formal service procedure for the court to serve a summons. The first way to serve a summons is for the parties to sign in person. Telephone notification is not a service mode.

Legal basis: Article 85 of the Civil Procedure Law of People's Republic of China (PRC): The service of litigation documents shall be directly delivered to the addressee. If the addressee is a citizen, I will not give it to his adult family to sign for it; If the addressee is a legal person or other organization, it shall be signed by the legal representative of the legal person, the principal responsible person of other organizations or the responsible person of the legal person or organization; If the addressee has an agent ad litem, he may send it to his agent for signature; If the addressee appoints an agent to the people's court, it shall send it to the agent for signature. The date of delivery is the date when the adult family members, legal persons or other organizations of the addressee are responsible for receiving and the litigation agent or agent signs for it.