Why can't I make an appointment for a health certificate on Monday?

The appointment time for the health certificate is from Monday to Friday, and it is full. Make an appointment online first. If the appointment date is gray, it means that the number of people who have made an appointment on that day is full, and other dates can be reserved. Health certificate refers to the proof of preventive health examination, which proves that the examinee has the health quality to engage in the prescribed business.