Hi @Brian Liu ,
May I know if you are not receiving banner notification for emails or calendar?
In new Outlook, go to Settings > click General > click Notifications and expand each section and share the screenshot with us.
Please expand the Notification section and ensure option 'Allow notifications to play sound' is turned on. Now, scroll down to the section Mail > for 'New email', select Desktop > play sound is on > same goes to for the sections 'Reactions and Mentions'.
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