A “small number” of iPhone 18 Pro Max units on AT&T’s network lose cellular connectivity because of an iOS 27 bug. This is not an intermittent problem, as the devices fail to reconnect to the network even after a reboot.
Apple recommended on Friday that all iPhone 18 Pro Max users update to iOS 27.0.1 to prevent the issue from happening in the future. But if your unit is already affected, you’ll need a replacement.
iPhone 18 Pro Max on AT&T: A dropped signal that never comes back
It’s one thing for an iPhone to lose cellular connectivity for a few minutes due to a software glitch. But some iPhone 18 Pro Max users on the AT&T network report losing cellular connectivity entirely. As a result, they can’t make or receive calls, send or receive texts, or use cellular data.
Apple acknowledged the problem and issued the following statement to MacRumors:
“We have identified an issue affecting a small number of iPhone 18 Pro Max users on the AT&T network that may cause a device to lose service and be unable to make calls. We released iOS 27.0.1 earlier this week and strongly encourage all iPhone 18 Pro Max users to update now, and are also issuing a carrier settings update today. These updates together are meant to help prevent this issue from occurring.”
If you own an iPhone 18 Pro Max on AT&T’s network, the updated AT&T carrier settings should automatically download within the next two weeks. If you can’t wait that long, manually grab the update by going to Settings > General > About.
Already affected? You’ll need a replacement.
However, these updates only help prevent the problem if it hasn’t already affected your iPhone 18 Pro Max. If your device is already failing to connect to AT&T’s network, you must get a replacement device. The company recommends contacting Apple Support, AT&T or visiting your nearest Apple Store to arrange a replacement.
Interestingly, iPhone 18 Pro Max units in the United States use the Qualcomm Snapdragon X80 modem instead of Apple’s in-house C2 modem found on the smaller iPhone 18 Pro. So, it is surprising to see the Pro Max units being hit with a connectivity issue rather than the smaller Pro model.
Rajesh has been writing about consumer technology for over a decade, with a strong focus on iPhones, Macs and Apple’s ecosystem. He enjoys digging into Apple software updates, hardware changes, and discovering new Mac apps that make work faster and more enjoyable.
You can reach out to him at mail[at]rajeshpandey.me.
