Using older versions of Outlook for Mac in business environments
I haven't seen a post describing the exact behavior with Outlook for Mac 16.113, but there is a similar discussion where users reported that Legacy Outlook search and filtering stopped working after an Outlook update, while New Outlook continued to return results: Outlook (Legacy) 16.109.1 update (MacOS) - Search and Filtering Broken - Microsoft Q&A
In that thread, the issue was ultimately resolved after completely removing Outlook data/profiles, reinstalling Outlook, reactivating Office, and re-adding the accounts.
While it is not the same version or scenario, it may be useful to compare symptoms and troubleshooting results.
I hope this helps.
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