Overview

• Apple updated its iMessage support page to explain a case where activation fails if the eSIM is set up after onboarding.
• When an eSIM is provisioned later in Settings, iMessage does not activate automatically and requires a manual reset.
• Affected users may see Not Delivered alerts, green SMS/RCS messages, or iMessages sent from an email address instead of a phone number.
• Apple advises opening Settings, tapping Apps, selecting Messages, turning iMessage off, waiting briefly, then turning it on and confirming the phone number before sending a test message.
• The guidance focuses on people who skipped eSIM activation during setup or installed a new eSIM after a carrier change, and it follows earlier iOS 26 activation issues noted this month.