July 30, 2018: 17:10 UTC - The issue has been resolved. AT&T will continue to monitor their services for any further issues.
July 28, 2018: 05:16 UTC - We have received confirmation from our service provider that service to AT&T customers has been restored. We will continue to monitor to ensure there are no further issues.
July 27, 2018: 21:23 UTC - AT&T is continuing to experience issues with their SMS service affecting all AT&T mobile phone customers. All major SMS vendors including Nexmo, Telesign, and Twilio, and all their customers, including SecureAuth, are impacted. At this time, AT&T does not have an ETA on when this issue will be fixed. SecureAuth will provide an update as soon as more information becomes available.
July 27, 2018: 16:41 UTC - AT&T is continuing to experience issues with their SMS service and we will provide an update as soon as more information becomes available.
July 27, 2018: 15:12 UTC - We have received reports of SMS latency issues to AT&T subscribers. We are investigating with our service provider and will provide updates as soon as they become available.