The issue that was affecting all Azure AD B2C customers has been mitigated. All customers should see their traffic returning to normal.
[Original Post at 1:44 PM PDT] We are investigating an outage that is currently affecting all Azure AD B2C customers. We are working to mitigate the issue.
[Update 2:00 PM PDT] The engineers are in the process of deploying a fix and will continue to monitor the issue.
[Update 2:20 PM PDT] Traffic is resuming to normal gradually to our datacenters. We are in the process of patching all of the datacenters.
[Update 2:35 PM PDT] The fix is still rolling out to all datacenters. Some customers should already be seeing service return to normal operations.
[Update 2:40 PM PDT] The fix has rolled out to most datacenters. We are working on fixing the rest of the datacenters and will continue to monitor the situation.
For updates, please see https://azure.microsoft.com/en-us/status/