AT&T sends text messages to some iPhone 18 Pro Max customers on its network warning that certain devices may not be able to complete calls, send or receive texts, or access data, including calls to 911. The carrier advises affected users to update to iOS 27.0.1 immediately via the iPhone’s Software Update settings.
Reporting from multiple outlets says many affected users who install the update report that it does not resolve the problem. Apple’s iOS 27.0.1 release notes are reported to not mention a fix for the AT&T cellular issue, and coverage citing user discussions describes symptoms such as inability to make or receive calls or connect for cellular service, slow text delivery, intermittent connection drops, and devices entering SOS mode.
Outlets also note uncertainty about the underlying cause. Some coverage highlights the iPhone 18 Pro Max on AT&T as the U.S. model using a Qualcomm cellular modem, while other models and regions use different modem hardware, but it remains unclear whether that contributes. Overall, AT&T acknowledges the issue and points to iOS 27.0.1, while user reports and release-note summaries raise doubts about whether the update fixes it.
