How do I fix a buggy install of N360?

N360 was updated to version 22.5.2.15 on 29th June. Since then I have had performance issues on my laptop with random freezes of 5 seconds or more, sometimes in quick succession and sometimes with up to 30 minutes between freezes. Also, N360 takes forever to load when I try to open it to investigate.
I initially suspected it was a problem with Firefox, but after uninstalling/reinstalling Firefox and disabling the Norton Toolbar, the problem with random freezes seemed to go away. However, N360 still takes forever to load when I try to open it and I suspect I have a buggy installation. I would like to uninstall/reinstall N360 but am nervous about doing this in case I mess up my licence. can anyobe advise whether there is a recommended way to uninstall/reinstall N360?