If I am understanding your post correctly, you are changing your phone number and you would like to make sure that your new number is associated with your Apple ID. I know it is important to make sure you can be reached for messages using your new phone number. I'll be happy to share the following article, Add or remove your phone number in Messages or FaceTime , that has some information on this:
Remove your phone number
If you don't want calls or messages for your iPhone on your iPad, iPod touch, or Mac, you can remove your phone number.
On your iPhone, go to Settings > Messages > Send & Receive. Sign out of your Apple ID account. Then go to Settings > FaceTime and sign out of your Apple ID account.
Then once you have your new number ported over, you can set it up:
Set up your phone number
These steps work only with the phone number that belongs to your iPhone, not the phone number of a landline or other device. On your iPhone:
- Go to Settings > Messages and make sure that iMessage is on. You might need to wait a moment for it to activate.
- Tap Send & Receive. If you see “Use your Apple ID for iMessage,” tap it and sign in with the same Apple ID that you use on your Mac, iPad, and iPod touch.
You can also add your new number to the Apple ID page, once you have signed out of the Apple ID on your device.
Apple ID Support
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