Additional purchased add-ons from this site should be initiated with a license key so as to get updates through the WordPress Dashboard. Your license key would be emailed to you after the confirmation of the purchase. if you’ve lost your key, you can recover it here: Get your license key.
You have to activate the Plugin from WordPress Dashboard->Plugins Section to activate the license. The following notice will appear once the plugin is activated:
Click the ‘Please enter your license key’, or search for the plugin in the list of plugins on the plugins screen and check these fields:
You should use the activation email associated with your key to make it work. To activate the key, check the current plugin checkbox and press enter.
Key Activation Limit Reached
In case the key activation limit is reached, you can login to your account and deactivate the keys. After login, you can go to “My Account” and click on “Account Dashboard” menu.
Then you can reactivate the key on the required site.