I have the same issue
See here https://status.azure.com/status/
WarningAuthentication errors across multiple Microsoft services - Investigating
SUMMARY OF IMPACT: Starting at approximately 19:15 UTC on 15 Mar 2021, a subset of customers may experience issues authenticating into Microsoft services, including Microsoft Teams, Office and/or Dynamics, Xbox Live, and the Azure Portal.
CURRENT STATUS: Engineering teams have been engaged and are currently investigating. The next update will be provided in 60 minutes or as events warrant.
This message was last updated at 19:58 UTC on 15 March 2021