Apple advises removing inactive SIM to fix iMessage on iOS 26

Apple this week published troubleshooting steps for iPhone users who cannot activate iMessage with their phone number after updating to iOS 26, saying the problem can occur when an inactive SIM or eSIM on the device shares the same phone number as the active SIM. Affected users may see sent iMessages fail with a Not Delivered alert, find texts are sent as green SMS or RCS bubbles instead of blue iMessage bubbles, or discover messages are sent from an email address rather than their phone number.

Apple’s support guidance explains that the issue typically arises when an inactive physical SIM or eSIM entry on the iPhone uses the same number as the active line. On some devices, the duplicate number may appear twice in the Messages Send & Receive settings, preventing the phone number from being selected to register with iMessage. While messages will continue to flow via SMS or RCS, iMessage-specific features tied to the phone number will not function until the number is reactivated.

To resolve the issue Apple advises users to remove the inactive SIM entry and then reactivate iMessage using their phone number. The company outlines a few simple steps: open the Settings app and tap...