Lightroom Classic 7.3: Doesn't apply correct Profile when using presets

Just installed the new LR 7.3.  When I click on the topmost preset (colour/natural) then the profile on the right-hand basic panel is listed as 'default Profile' and also '! Profile missing'.  This does not change even when I click on a different preset which has a 'profile' in the settings.  In fact, applying any of my presets will bring up the '! profile missing' warning.  If I subsequently reset the image settings, the presets will apply the correct 'profile'.

After some experimentation, it seems that applying any of the presets in the first 'colour' section (natural, bright, high contrast, vivid, matte) causes this problem.  

I can understand that maybe there is a missing profile in my system, but I can't understand why clicking on these presets would subsequently render all of my perfectly good presets useless.