Using Catalina either very slow startup or not working

Have been using LibreOffice for some months even when Catalina first came out.
However, last couple of weeks getting very slow and eventually would not start. Uninstalled and used 6.35
without much success. Uninstalled again with now 6.41. Marginally better but after returning from holiday
(switched off mac) , back to square 1.
Some similar posts go back to 2019, but cannot find any upto date solution. I assume other users must be
having same problem ? or is it a mac problem.
Last throw of the dice before I try another similar office type prog.

For what’s it worth here is an update. First tried reinstalling catalina,but still had problems.
Then uninstalled Libre and making sure deleted all files .
Then reinstalled Catalina and finally clean install of libre. This seems more reliable although
I am holding off rebooting.

I reinstalled it and it is working very fast