Taking a look at the sitemap.xml generated by this plugin, i can see that most of the url in it are those including search params

like this one for example :

<url>
    <loc>https://mydomain.com/search/category,appartement/country,France/region,G%C3%A9rardmer/city,G%C3%A9rardmer+-+centre</loc>
    <lastmod>2021-01-04</lastmod>
    <changefreq>hourly</changefreq>
  </url>

In the meantime, there is an instruction in search.php to "Noindex" those URLs ...

Is there another recent version of this plugin ? is there a mean to modify generated URLs ?

Otherwise, i think the best advice is DO NOT USE THIS PLUGIN
 
Using it means you ask Google to come every hour to inspect a file you don't allow it  to index