Build 9.0.23140 update de-activates Parallels

My copy of Parallels 9 urged me to install this update. I did. And now my copy of Parallels is no longer activated. According to the "About Box" it says: "This copy of Parallels Desktop is current not active." I can find no way to activate it. It offers me a "Buy" button, but no place to enter my activation key. Does anyone know how to coerce this program into accepting an activation key? It is extremely frustrating to lose access to my windows programs.