Bloomberg reported Oct 3 that Apple said a fault affecting a small number of AT&T iPhone 18 Pro Max users may cause devices to lose cellular service and be unable to make calls; affected units will require replacement. Apple has issued a carrier-settings update and released iOS 27.0.1 to prevent further spread. The carrier-settings fix will auto-download for AT&T users within 14 days; Apple advises users to install available software updates immediately.