Auto refresh or sync is not working in outlook calendar

Question

Hi,
I've manually imported a calendar URL into my Outlook calendar, and initially, the events loaded successfully. However, I've noticed that any changes, such as removing or adding events in my app's calendar or editing existing events, are not being reflected in the Outlook calendar. I've added code to refresh my iCal file every two minutes using REFRESH-INTERVAL:PT2M, but unfortunately, this doesn't seem to resolve the issue.
I'm seeking assistance for the following:

• Is there specific code that needs to be added to the iCal file to notify the Outlook calendar for an automatic refresh or synchronization with the existing data?
• If there's no solution for frequent refreshes when manually importing a URL into the Outlook calendar, could you please provide information what is the default time interval that Outlook uses to automatically refresh its manually added calendar URLs?

I appreciate any guidance or suggestions to resolve this issue.