After purchasing the plugin, you should have received an e-mail indicating the premium version of the plugin, as well as a key code. The key code can only be entered once. Therefore, you may only use the premium version of the plugin on one domain.
On your dashboard, after clicking the plugin on your sidebar, you will be able to enter your key code in the key code area. You will then submit it to activate your premium version.
If you want to change domains, please e-mail us at firstname.lastname@example.org, with the subject title “Key code release” and let us know the plugin bought and the e-mail that has been used for the purchase. As soon as we receive the e-mail, we will notify you when we have released the key code. You will then be able to use it on a new domain.