Smartphone menu dissapears

Hi,
Normally, if I scale down the browser window, the menu changes to a compact version for smartphones. However, I noticed that when this plugin is active that the site’s menu bar disappears on phones or if I scale down the browser window. As soon as I deactivate the plugin, everything is back to normal again.

Does anyone know how to solve this?

https://www.ads-software.com/plugins/photo-gallery/