Hi @William Wolfe ,
Welcome to our forum!
In order to verify, Where did you search? In Outlook, there are two search boxes, given your case, the problem might be that you used the search people box.
More information about how to Use Outlook's built-in search filters in this article for your reference: How to search in Outlook
If this is not your case, what detailed version of Outlook are you using(File > Office Account > About Outlook)?
Some issues will be resolved after the program is updated. Make sure that you get the latest update, choose File > Office Account > Update Options > Update Now
If you need more help on this, feel free to contact me.
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