Multiple search in one page bug

Hi, I’m using your plugin which I find very useful and well done, it was just what I was looking for.
I only noticed a small bug, if you put more search bars on the same page, the search starts in both bars, you can see an example on this site: https://www.vistonline.it/new/
in the section “Visti sui passaporti” and “Legalizzazione documenti”.
There is a way to fix this?
Thank you

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