How can children have Phnom Penh instead of Phnom Penh?

The operation to prevent children from having a health code with Phnom Penh is to vaccinate COVID-19 vaccine all the time, and Phnom Penh will appear around the health code.

This golden health code only adds a thin golden border and vaccination information on the basis of the original green code, instead of turning the whole code into gold, the injection and shield are added in the upper left corner, indicating that the holder has been protected by COVID-19 vaccine.