Hey @ArielTo! I just did some testing with my own Google Calendar connection using the “Event Start” trigger and was able to access events on a read-only calendar I was invited to as well as one I subscribed to.
I see you wrote into support about this and that you’re subscribed to a sports schedule calendar and because the schedule is already fixed, there are no changes/updates to trigger your Zap.
I am going to copy/paste relevant parts of their response to you for anyone following along that is running into a similar issue:
It looks like there's no way to add or update events in this kind of calendar since you we don't have the correct permissions. Using this calendar will not be possible since we're using the "New or Updated Event" trigger.
Workaround: This may require time to complete. We could create a personal calendar in your Google Calendar account and manually copy the events one by one (to trigger your Zap). This is the only option for calendars we don't have "write" permissions for.