A recent update caused an issue in the Outlook client where the "sender" name is not appearing in search results. As a workaround users can search using Outlook on the web.
The vendor, Microsoft, is deploying a fix but there is no estimated time to resolution.
If you have questions about this issue or would like to report additional service impacts please contact the OIT Service Desk: https://oit.duke.edu/help
For more information about Office 365 visit OIT's web page: https://oit.duke.edu/what-we-do/applications/office-365