Overview
- Apple confirmed a small number of iPhone 18 Pro Max units on the AT&T network can lose cellular service and display an “SOS” indicator, leaving them unable to make calls, send texts, or use mobile data while Wi‑Fi still works.
- Both companies have rolled out iOS 27.0.1 and an AT&T carrier settings update that they say will prevent new occurrences but will not reactivate phones that are already experiencing the problem.
- Apple and AT&T instruct affected customers to contact Apple Support or AT&T or visit an Apple Store or AT&T retail location to receive a free replacement device that already has the updates installed.
- Reporting notes a U.S. hardware difference — the iPhone 18 Pro Max ships with a Qualcomm Snapdragon X80 modem while other 18 models use Apple’s C2 modem — but Apple and AT&T have not confirmed whether the modem, carrier configuration, or software interaction is the root cause.
- The replacement approach is being handled through stores and support channels rather than a formal recall or named service program, and users who are not yet affected are advised to install iOS 27.0.1 and trigger the AT&T carrier update via Settings > General > About.