iOS Calendar with Exclamation Point at Bottom

As you suggested , I taped and saw that there was a verification error in some calendars I subscribe to in my Google account:

I tapped on the text “Verify Account Information”, a link was displayed, I tapped on Ok and closed the page.

the exclamation point is gone now.

However …

I recently subscribed to several additional calendars on my Google account and these new calendars aren’t listed here in the iOS Calendar app. (Yes, older Google Calendar subscriptions are listed. Yes, my iOS Mail, Calendar, Contacts, and Notes sync with my Google account and seem to be updating just fine. Even the content of the new Google Calendar subscriptions shows up within my iOS Calendar app. It’s just that the new subscription names aren’t listed on this screen.)

Do you have any idea how to get these new Google Calendar subscriptions listed here in iOS Calendar?

I figured it out: I didn't select in my Google settings to sync the missing calendars here

https://calendar.google.com/calendar/u/0/iphoneselect