This tip will teach you how to add custom help desk information to Office 365–users will be able to select the ?/Help button next to their user icon, and see your organization’s help desk information in addition to Microsoft help.
Sign in to portal.office.com, then select Admin:
Select Settings, then “Organization Profile”:
Select the “Edit” button next to “Provide customized help desk contact info”:
Enable the help desk card if necessary, then add information: