A few more things I can think of, that may cause this issue
– Have you re-created the index table after the change? https://i.imgur.com/lWLKvql.png
– Is the index table engine selected on the search instance General Options panel? https://i.imgur.com/WfwcN0R.png
– Are the exact matches Disabled? https://i.imgur.com/Ho1KnGI.png
This is a very likely issue. I'm planning to add a warning message there, whenever the index table is enabled and the user tries to enable this option. It's very easy to miss that small warning message at the bottom.
As an alternative for exact matching for the index table, I recommend the following configuration: https://i.imgur.com/S9XdpCH.png
You can even turn off the Secondary Logic there, if you feel like there are too many results returned.
Please check these, and let me know if any of the suggestions worked.Best,
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