Does iPhone 2020 SE support Google Calendar at all?
It looks like Google/Apple supports it if you're using the latest versions of iOS. Maybe some settings aren't correct on your iPhone?
Go to Settings. Scroll down to Calendar. Select Accounts. At the bottom is &quot;Fetch New Data&quot; Is Push turned on? Also in the list above this you will see some Accounts. What are your settings for Gmail? Fetch &gt; Manual or Fetch ?
Under Settings, Cellular. Is Calendar enabled for use with Cellular? If not and you aren't near a hotspot this could cause your calendar to stop updating.
Google Calendar features that don't work on Apple Calendar;

Email notifications for events

Is this what you were waiting for? An event change notification?

Create new Google calendars

Room Scheduler


The work around would be to use the Google Calendar App in order to get the notifications of event changes.