Hmm, in that case it is very likely that either another plugin or the theme itself has a manual override. If you have any other search plugins installed that can affect the search results, then it is very likely the issue.
If not, then it's more problematic, as there might be a custom query coded into the theme itself, which cannot be overridden. In this case, you can add temporary FTP and back-end details, and I can check on the files directly. If possible, I might be able to disable the custom query to enable the override.Best,
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