This means multiple people can share the same Apple ID and still route text messages to specific devices.
First, go into your iPhone or iPad's settings.
Next, scroll down the left-side menu and tap on "Messages".
In the middle of the Messages settings, tap the "Send & Receive" button.
This screen will list the phone numbers and email addresses associated with the Apple ID account. Simply uncheck the phone number or email account you want to block from iMessage.
According to Apple, we are doing it wrong in the first place. Officially, we should be using a separate Apple ID for each person and connect them using the Family Sharing feature.
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