How does Unicom send the last 4 digits of ID card?

Edit the number you want to inquire after the letter # and the four digits after the ID card.

Edit the last four digits of the short message CXMYD# ID number as 1000 1, and reply Y with authorization to realize "roaming place query", which can query the route information of mobile phone number in the past 15 days without providing accurate location, stay time, etc.