Hi @KELLY CLARK
Welcome to our forum!
What is your account? Outlook.com or something else?
May I understand that you want to log in with ******@xyz.com and send and receive emails with ******@xyz.com?
If so, you may set @xyz.com as primary account and then go to Sign-in preferences to untick the @xyz.com. After that you can use your alias (@xyz.com) for signing in while keeping your primary email address (@xyz.com) for sending and receiving emails.
By the way, when composing an email in Outlook, ensure that you select your primary email address (******@xyz.com) when sending emails.
More information: Send email from a different address in Outlook.com - Microsoft Support
Hope it helps!
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