The main issue is that the plugin is not visible anywhere on the page. I see it is installed, but it is not in use. The search bar on the top of the page is the theme default. I guess you had the plugin search in that position?
If you used the search shortcode somewhere, and there was a theme upgrade, it is possible that it had been replaced with the default one.
May I ask what previous version were you using of the plugin?
Because your purchase date shows me yesterday (04/10/2017), and if you had a very old, or modified version, it is possible that you will have to check the plugin configuration as well.
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