1. Apply for Entry Registration Certificate in relevant institutions: You can submit an application to relevant institutions (such as entry-exit administration departments or border checkpoints) to obtain your Entry Registration Certificate. Generally speaking, this application process requires the applicant to be present in person or entrust others to handle it on his behalf, and provide some supporting materials to confirm your identity and entry record.
2. Inquire with the entry-exit agencies: If you need to inquire about the specific entry-exit time and place, and there is no record in your passport, you can consult with the entry-exit agencies and inquire about the records. Generally speaking, you need to provide personal identification information such as name, nationality and passport number to get more detailed query results.
3. Explain the problem: If you can't prove your entry record, you generally need to consider accepting other restrictions or secondary instructions, such as investigation or additional review. This usually requires other means to prove that you have been to the country, such as shopping, air tickets or hotel accommodation records, or to find some friends in the country to prove that you have been there.
It should be noted that different countries and regions may have different regulations and procedures, so you should operate according to the requirements of relevant departments in your country or region.