Here's what fixed it for me (macOS Monterey 12.1 on MacBook Pro (14-inch 2021); Outlook 16.56.
Switched to "New Outlook"
Go to Preferences.
Go to Accounts.
Select your Default Account.
At the bottom of the left column, to the right of the + and - minus signs, click on the circle with three dots inside.
Select Reset account.
This worked. Unfortunately I am not a fan of the "New Outlook," but at least my search functions are back.
We'll see if it doesn't break over time.
Alexphil
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