Thank you very much for choosing our theme and for contacting us.
Please, provide your site admin access to the private area.
Make the full backup of your site and confirm the permit for us to deactivate the plugins not related to the theme and switch to the parent theme for the while of checking what may take up to 15 minutes.
Megamenu is not supported in mobile as there is not space enough. You need to create another menu without megamenu blocks (it can be a multi-level menu) and assign it to the mobile menu.