Whenever it appears to the minor’s parent or guardian, or the principal of the school which the minor attends, a principal in the municipality in which the minor resides, or the labor commissioner or the commissioner’s agent or representative who issued an employment certificate, or to the person‘s successor, that such certificate has been improperly or illegally issued or that the physical or moral welfare of the minor would be best served by the revocation of the certificate, such certificate may be revoked. The revoking officer shall give notice of the    revocation by registered or certified mail to the person employing such minor and to the minor holding the certificate. Immediately upon receiving notice of the revocation of the certificate, the employer shall return the revoked certificate to the officer revoking the same and shall discontinue the employment of the minor. Revocation of a permit must be registered with the labor commissioner or the commissioner’s agent within ten days.