If the update is not working for you, please try refreshing both the product manager and the plugins page a couple of times. If that does not help, please open a ticket and send some login credentials and a link to your wp-admin and we'll take a look at it (also to find the cause and maybe fix it for the future).
At the moment the update feature is not working. Our apologies about that. We are working on an update that will fix this.
Please update manually: Download the plugin again from envato, uninstall the old version and install the one via the wordpress plugin page. No data will be lost.