How to register new number to iMessage
How do I register my new number to activate iMessage for my new number
iPhone 8 Plus, iOS 14
User profile for user:
Community User
First make sure your SIM card with your new phone number is in your iPhone.
Go to:
Settings -> Apple ID (Your Name) -> Name, Phone Numbers, Email.
Press Edit, add your new phone number if it has not already been registered.
After, go to:
Settings -> Messages. Activate iMessage and check that your new number is in the Send & Receive menu.