It would be helpful if you stated what version of Lightroom you were using previously and what version you have now. Telling us they're the same doesn't provide any clues as to the possible cause.
Go to the help menu in LR and select System Info and post the first 5 lines of text that comes up.
Lightroom Classic version: 7.2 [ 1156743 ]
License: Creative Cloud
Language setting: en
Operating system: Mac OS 10
Version: 10.11.6 [15G31]
Ive tried force quitting the app, rebooting the machine etc...
Ok it finally worked after about six attempts. Must have been some conflict somewhere.
Kind of regretting spending a pile of money on presets recently...i like the look of the profiles.