Hey Tom,
Thanks for posting to the Q&A board. I have a couple questions I'd like to ask to gain clarification on your issue:
- What Teams environment are you experiencing this on?
- Is the issue appearing in multiple environments?
- Are you looking for an internal or an external Team?
As an FYI, you are unable to join an external team until you are invited and added as a guest user to the O365 tenant you are trying to reach out to. You can read more about it here: