Membership Lite vs. Membership Premium

I am really confused. I hope you guys can help me.... I was told that I need to uninstall Membership Lite & install Membership Premium from the support team. I do not know how to do this at all, or where to find Premium? There was only 1 choice that I could see when I signed up and paid the 19 dollars for the pluggin. Obviously, I am new to the whole pluggin WP thing. There is no distinction on your site about these 2 different versions. Where on your site does it talk about this?