Download Update Plugin : https://support.wedesignthemes.com/updated-plugins/
The plugin is already activated and please ignore the message that is showing in your dashboard.
Plugins are included in our theme package, there is no need for you to purchase them. However if you want premium features of the plugin and premium support, only then you need to purchase a separate license for it.
More info can be read here : http://docs.wedesignthemes.com/dt_articles/how-to-get-updated-theme-premium-plugins/