How can I switch from SMS to iMessage on a new iPhone?
I set up my new phone but can’t send in iMessage system (blue message instead of green). Know do I change back to blue
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iPhone 15 Plus, iOS 18
Have you logged into iMessage? Do you have an active data connection (WiFi or cellular)? Is the person (or persons) you're messaging also an iMessage user?
Set up Messages on iPhone - Apple Support