Hi @Daniel_Barra, I tested a bit and could reproduce this.
The Google Calendar Trigger node would not trigger for “Event Created” when you’re being invited to an older existing event created by someone else. In such cases, the created date of the event (which is what the node uses to identify new events) remains whatever it was when the event owner first created it.
So to have your trigger run for these events as well you would need to pick Event Updated in the Trigger On field of your node (as the updated timestamp of such an event does change in the aforementioned case).