Follow the steps at your own pace

1. Open the customer list and choose customer import.
2. In the phone app, choose contacts and grant read permission; in a browser, choose a file.
3. Use a UTF-8 CSV or TXT file with comma-separated values and the headers name, phone and email. Email is optional.
4. Review the loaded list and phone numbers before importing.
5. Check the import summary and customer list, then address rows that were not imported.