LR does not see PS in the external editor preference box, states "PS can not be found"

Recent updates to LR and PS to most current versions on my M1 Studio desk top has severed the connections between the two applications. In my LR preferences dialouge box for external editors, LR states that it can not find Photoshop, and therefore I can not entere a version in the selection box.  PS runs independetly just fine.  Topaz plug ins are still recognized but not PS. How to re connect so I can 'edit in' PS again.  Thanks   Also I have dumped and reinstalled fresh versions of both LR and PS to try and correct the situations  to no avail.  THanks again in advance for any help offered. 

[moved from bugs to discussions according to the community rules - Mod.]