The lock file could not be opened for exclusive access by LibreOffice, due to missing permission to create a lock file on that location or lack of free disk space.
I haven't a lot of free space - 10GB but that should be enough to open a 2 row test file.
I was trying a simple test before recommending Base to an inexpert user, at the moment I can't do so, unless there is a very simple way to fix this. I've had this sort of thing happen with other Snaps, so I'm inclined to stick to debs where possible in future.
sudo apt install libreoffice
– Archisman Panigrahi Jan 14 '20 at 17:37