Google Calendar is a great tool for collaborating with teams. Sometimes new email addresses are blocked by Google Calendar until they are known to mitigate spam.
In order to receive all calendar invites straight from your favorite calendar app, you need to allow invitations from all senders. This is easily done by navigating to calendar.google.com going to:
Settings --> General --> Event Settings
And Look for the "add invitations to my calendar" option.
Then select the "from everyone" option.
Here is a video showing all steps completed: