1. Confirm receipt of the certificate from the Maritime Safety Administration. Usually, the maritime safety administration will provide a courier number or logistics number when mailing the certificate.
2. If you haven't received the courier number or lost it, you can call the Maritime Safety Administration for telephone consultation to find out the delivery of the certificate and the specific courier information.
3. If you already know the name of the courier company, you can enter the ID number and the recipient's name on the "Express Inquiry" or "Logistics Inquiry" page through the courier company official website to inquire about the courier status and logistics information.
4. When inquiring the single number, please confirm whether the name of the courier company and the single number you entered are correct, so as not to find the result.
If you can't find the license number through the above methods, I suggest you contact the maritime safety administration or the courier company directly for consultation.