Apple has published a new support document explaining a glitch in iOS 26 that stops iMessage from activating with some users’ phone numbers. The problem, reported since the update rolled out last month, affects iPhones with both an active SIM and an inactive SIM linked to the same number.
If you’re suddenly seeing green message bubbles or messages sent from your email instead of your phone number, you’re likely dealing with this bug.
What’s Causing the iMessage Glitch
According to Apple’s support page, the issue occurs when an iPhone has an inactive SIM card, physical or eSIM that shares the same number as the active one. This can confuse the iMessage activation system, preventing your number from linking properly.
Affected users have reported several frustrating issues: messages failing to send with a “Not Delivered” error, conversations reverting to SMS or RCS instead of iMessage, and outgoing messages being delivered from an email address. In some cases, the same number appears twice under the Messages settings.
The bug appears most often on devices that have switched carriers, changed SIM configurations, or migrated from a physical SIM to an eSIM without deleting the old one. Apple says that removing the inactive SIM resolves the issue in most cases.
How to Fix iMessage Activation Problems
If your iPhone is affected, the solution is straightforward. Apple’s support team outlines a step-by-step fix:
- 1. Check for duplicate SIM entries:
- Open the Settings app and go to Cellular.
- Look for two SIMs showing the same phone number.
- 2. Remove the inactive SIM:
- If the inactive SIM is physical, eject and remove it.
- If it’s an eSIM, tap Delete eSIM to remove it.
- 3. Re-activate iMessage:
- Return to Settings and select Apps.
- Tap Messages, then Send & Receive.
- Tap your phone number to reactivate iMessage.
After following these steps, iMessage should resume using your phone number as normal. Most users report that the changes take effect immediately, but in some cases, it can take a few minutes for the system to update.
Apple’s iOS 26 Rollout
The iMessage bug is one of the few notable issues following the iOS 26 release, which introduced several under-the-hood changes and security updates. While it doesn’t affect every user, those relying on dual SIM configurations are more likely to encounter it. Apple hasn’t said whether a future update will eliminate the issue altogether, but the workaround appears to be a reliable solution for now.
If you recently updated to iOS 26 and noticed your messages turning green or your phone number missing from iMessage, check your SIM settings first. Removing an outdated SIM might be all it takes to get your iPhone messaging normally again.
