Microsoft is reporting users having issues creating and joining Microsoft Teams meetings.
We're investigating an issue where users in Europe may not be able to join or create meetings. For more details, please look for TM292507 in the admin center.
— Microsoft 365 Status (@MSFT365Status) October 19, 2021
The issue appears to be primarily affecting the European region and seems to be running for at least 2 hrs.
Microsoft is currently investigating the issue.