Hi @IBN
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How do i stop the User email address from carrying ".Onmicrosoft.com" when searching them on Teams Search
Do you have any operations to this user's domain before?
Do you mean you want to change this user email address (onmicrosoft.com) to another custom domain?
Please notice that you cannot change the name of your initial .onmicrosoft.com domain. So if you want to change this user's domain, you need to have at least one custom domain that you've added to Microsoft 365 before you can choose a default domain. For more details about its steps, you could refer to this article.
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