Automatically import tracking numbers to AfterShip using Google Drive Spreadsheet via CSV Auto - Fetch.
You can use google spreadsheet to use the csv auto-fetch option.

Prepare auto-fetch file

Download the AfterShip CSV Sample
Create a new Google spreadsheet
Copy from sample csv and paste the fields within newly created sheet
Enter the required data within the Google spreadsheet
Select Share
Choose option Anyone with the link can view

Upload the sheet

Go to Account Store Connection
Click on + New Connection
Select CSV Auto Fetch on next screen
Paste the Google sheet link
Update daily import time as required
Click Connect