Microsoft has actually posted status regarding this issue:
https://status.cloud.microsoft/
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Our services aren't available right now
What's going on???**
There is an issue with Teams presence and login servers.
Teams works if already signed in, but new logins are not possible. There is nothing you can do on your side. The issue must be fixed by Microsoft.
The error message "Our services aren't available right now" typically indicates an issue with the Azure Front Door route configuration. To resolve this, you should check the status of the default-route. If it is disabled, enabling the route may help restore service availability.
Additionally, ensure that your custom URL domain is properly configured and that there are no underlying issues with the service itself. If the problem persists, it may be worth checking for any service outages or maintenance notifications from Microsoft.
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