Thanks for responding. Let me clarify:
I actually did that a few months ago on an old Wordpress site. I have since closed that wordpress site and I have opened another. I wanted to transfer my Pro License from my old site to my new one.
However, when I use this key to validate it, it does not give me the Pro version
I have updated the domain and used the Pro version key, but still have the old version of the Xtheme.