Hi @Bradley Wilson ,
Is this a suddenly occurred issue?
Does it affect others in the same environment as you?
In case it's due to any corrupted configurations of the existing Outlook profile, please try creating a new Outlook profile and then add the email account again to see if it can work as expected. For steps of creating a new Outlook profile, you may refer to Overview of Outlook e-mail profiles-Create a new profile. Also remember to configure Outlook to prompt you to choose a profile when started so that you can choose the new profile next time.
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