I received a short message today, saying that my express mail could not be delivered because the address was unknown. I called and said there were illegal drugs in it. How did this happen?

This is phone fraud, don't believe it. There are many such cases on the Internet. Criminals, as post office staff, notify the victims by SMS, leaving their local telephone numbers, telling them that there are drugs and bank cards in the parcel, and then asking the victims to upgrade their bank cards on the grounds of preventing the funds in the bank cards from being stolen, and then providing a new bank card number in the name of the China Banking Regulatory Commission, so that the victims can transfer the money to the card number provided by the other party.