You use old version of the theme. Please update to the latest.
Don’t forget to make backup your site before updating.
Here is video tutorial how to update theme: https://www.youtube.com/watch?v=KdWESIIPU1k
Second step, please update your plugins (Revolution Slider, WooCommerce, WPBakery Visual Composer).
You can download the latest plugins versions at this link http://www.8theme.com/download-plugins/ ,
enter your purchase code of the theme to get the plugins.