Microsoft seems to have resolved the problem with Azure AD, operations should not longer be affected.

Microsoft Engineering teams have rolled out a fix to all affected regions. Internal telemetry and customer reports suggests that the error rate for dependent services is rapidly decreasing. Microsoft services are starting to see signs of recovery. Some services and offerings may have varying times of recovery following the underlying fix.

More details: https://status.azure.com

We are continuing to work on a fix for this issue.

Microsoft Engineering teams have rolled out a fix to all affected regions. Internal telemetry and customer reports suggests that the error rate for dependent services is rapidly decreasing. Microsoft services are starting to see signs of recovery. Some services and offerings may have varying times of recovery following the underlying fix. The next update will be provided in 60 minutes or as events warrant.

Microsoft has mitigated some Azure AD tenants, certains ClearID Customers with SSO can now authenticate successfully to ClearID.

An issue reported by Microsoft causes logins to fail with Azure Active Directory. Microsoft is investigating the issue at the moment.
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https://status.azure.com

The issue has been identified and a fix is being implemented.

An issue reported by Microsoft causes logins to fail in ClearID because there's a problem with Microsoft Azure Active Directory.