If you have changed sites and want to activate the license of an extension on another site, or you want to activate your extension on another site, you must first deregister the license on the site on which you activated it.

To proceed, press the ‘Deregister this License Key’ button, at this point you can always register the same license wherever you want!

To activate the extension on another site you will first need to install and activate the relevant extension.
On the site where you deregistered the license, the PRO options of the extension will no longer be available, even if the extension remains activated!