Additional features, settings, or issues not covered by specific Microsoft Teams categories
I am having the same issue. When a Teams was created, it did not create the calendar and I can't get to the mail in Outlook. If I create a O365 first, the calendar and accessing the mail works fine. What changed with MS? I thought they were all connected and if you created a Teams, it creates an O365 Group which includes the mailbox. But it doesn't seem to be the case in this particular Teams that was created. How can this be resolved?
Here is what it used to be: