Hi Drew,
Please carry out the following troubleshooting steps, as mentioned by our development team:
1) Check whether the button trigger option value is #responsive-menu-pro-button
2) Your website has a cache plugin. Please clear your cache plugin’s cache content and disable it during troubleshooting.
3) Disable one plugin at a time and clear browser history before re-visiting the menu and check if it works properly. If it work, that is the plugin that is causing conflict.
4) Switch to a WordPress default theme and clear browser history before re-visiting the menu and check if it works properly. If it works, that will be a conflict with the theme.
Regards,
Kriti