Hi @Alan Helton
Welcome to our forum!
As i know: The primary account is the one that you set up your profile with the first Exchange account you added to your Outlook. You cannot set another account as the primary account (The setting is simply to set it as the default outgoing email address).
To achieve what you need needs to remove the second one first and add then remove the primary account. After that you can create a new profile with another account making it the primary account. Alternatively, you can simply create a new profile and add a non-admin user's account to make it the primary account.
Hope it helps.
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