[Mitigated Sep 4] Customers unable to authenticate to Azure AD B2C

Between 0930h and 1800h UTC,  A very small set of Azure AD B2C Directory administrators experienced intermittent failures accessing the Azure AD B2C blades and some end-users had intermittent failed authentications.  Users who retried, were likely able to authenticate and access the protected resources.  The issue has been mitigated. Only a few B2C tenants were…