AT&T has confirmed reports of outages across its network in the U.S., and has instructed users to restart their devices to restore connectivity.
Reports had been circulating since 6:00 p.m. Eastern time regarding potential outages. At the time, device restarts weren't sufficient to restore connectivity.
AT&T confirmed the outage to AppleInsider just before 9:00 p.m. The carrier advised users to restart devices -- but social media reports suggest that it may not rectify the issue in every case.
Thanks for reaching out and making sure we're aware of your wireless service issues. If you're currently experiencing issue when making wireless calls, please restart your device - that should resolve the issue. Thanks for your patience & understanding. We're here for you! ^NdyE
-- AT&T (@ATT) November 16, 2017
Follow-on advice issued by AT&T suggests that multiple resets may be required to restore service.
If you've experienced an issue when making wireless calls, please restart your device, this might be required multiple times- that should resolve the issue.
-- AT&T (@ATT) November 16, 2017
Wi-Fi calling is unaffected by the outage, AppleInsider has also learned that older iPhones limited to 3G networks are also unaffected. Outages do not appear to be limited to any geographical area.