Some Apple iPhone 18 Pro Max users will need to replace their brand-new smartphones if they’ve suffered a loss of service issue. Everyone else on AT&T should update their software pronto to avoid the issue, Apple has said. Here are the full details.

Apple iPhone 18 Pro Max And AT&T: The Issue

“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,” Apple said in a statement shared with 9to5Mac .

The issue meant the phones were unable to connect to the AT&T network for calls, nor for text messages and data.

Apple iPhone 18 Pro Max And AT&T: Software Prevention

So, what should you do if you’re an AT&T customer who hasn’t yet had a problem? First of all, don’t panic. The issue only affects the iPhone 18 Pro Max, not the smaller iPhone 18 Pro and no other models of iPhone.

What’s more, Apple’s comment that the problem has only affected a small number is reassuring.

What you should do, Apple says, is update your iPhone to the latest software release, iOS 27.0.1, straight away. You can read full details of this release here and whether it’s stable enough to upgrade to here . “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,” Apple explained.

To install iOS 27.0.1, open the Settings app, go to General, then Software Update and choose Download and Install. As for the carrier settings, these should download automatically but can be triggered by going to the Settings app again, then General and then About.

Apple iPhone 18 Pro Max And AT&T: What To Do If Affected

The software update and carrier settings are designed to prevent future issues for AT&T users, but won’t help restore service to those iPhones that have lost it.

“Apple says that iPhone 18 Pro Max users who have already lost service will need a hardware replacement. Those users should contact Apple Support or AT&T, or visit an Apple Store or AT&T location,” 9to5Mac went on.

What’s not yet clear is whether it’s the modem in the phone that has caused the issue. The iPhone 18 Pro — and all iPhone 18 Pro Max handsets released outside the U.S. — use the Apple C2 modem. Only iPhone 18 Pro Max models in the States use a Qualcomm modem. The iPhone Duo, on sale from Oct. 23 , uses the Apple C2 modem.