[RESOLVED] Microsoft MFA SMS messages not being received

Microsoft posted an update to their advisory indicating service has been restored:

Service Restored

More info: Users were recommended to use voice calls or non-telecom authentication methods to complete Multi-Factor Authentication.

Final status: We’ve confirmed with the 3rd party cellular provider in the United States that impact has been mitigated.

Scope of impact: Impact was specific to users who were subscribers of the impacted 3rd party cellular provider.