AT&T and Apple are taking action today as they try to resolve iPhone 18 Pro Max cellular issues, according to MacRumors contributor Aaron Perris.

Thousands of iPhone 18 Pro Max users have been unable to connect to the AT&T network for phone calls, text messages, and data. The underlying cause has yet to be disclosed, but AT&T and Apple continue to work toward a resolution.

First, Apple today released an AT&T carrier settings update (version 72.1, up from 72.0.2) for iPhones. Given the timing of this update, it presumably includes some optimizations related to iPhone 18 Pro Max cellular connectivity, but it is unclear if AT&T has fully resolved the issues or if further tweaks will be necessary.

When a carrier settings update is available on your iPhone, you will be prompted to install it. If you dismiss the notification or do not see it, open the Settings app, tap General → About, and the update should appear there. You can see your iPhone’s current carrier settings version in the same About menu, next to your carrier’s name.

Second, Apple today started requiring iPhone 18 Pro Max users to install iOS 27.0.1 in order to set up the device, even though most if not all affected users have said that the update does not resolve the issues. A leaked AT&T email said iOS 27.0.1 is meant to help mitigate future impacts, so it may still help in some way.

In a statement shared with MacRumors today, AT&T said it is “working with Apple” on this.

Apple did not respond to our request for comment.

It is not yet clear if a follow-up update like iOS 27.0.2 will be required as part of a fix, or if the carrier update alone will be sufficient.