Hi,
Sure!
Looking at your page source, some critical scripts are loaded via a “defer” attribute, including jQuery and jQuery migrate: https://i.imgur.com/cZdnbhr.png
This is very likely the cause of the issue, as jQuery is not yet loaded, when the plugin tries to initialize the “select” script, resulting in an error.
If you have a page script minification/optimization plugin active, then I recommend optimizing the configuration, so the above the fold scripts in the header are not defered.