How to add your dynamic calendar to Google Calendar?

Question

PHP

On the server side, we generate a "calendar" in the .ics format using the URL.
The data, of course, is always up-to-date and is constantly updated.
Google Calendar has the ability to load this calendar by URL. However, it seems to be static and the data is not updated. But it still needs to be updated regularly.
How to achieve this?
Thank you.