The health certificate is handled in a regular hospital. If you pass the physical examination, that is to say, your health is fine, you can apply for a health certificate. If the doctor asks for a re-examination, you should ask what the specific problem is, whether the test results are in doubt or missing, or whether the doctor deliberately finds fault.
There is doubt about the handling method. You really need to re-examine this and take responsibility for your health. If the result is lost, it is necessary to re-examine, but the cost is borne by the hospital. If the doctor deliberately finds fault, he will directly hit the board.