Deleting old OneDrive files

Doing a bit of clean-up.

I worked for a company where I had access to their ONEDRIVE and I used to sync with it. It has created 20gb or so of files on my hdd. They stopped working with ONEDRIVE about 6 months ago so the syncing stopped, we now use a cloud-based solution and I do not need to have local copies anymore. So I am cleaning my machine a little and trying to delete the ONEDRIVE files as they are simply not required on my local machine, I'd quite like the 20gb back.. :-)

The issue - Some of them I can and have deleted but many of the files are coming up with an error message saying that I can not due to permissions. I am the admin of my machine and should have full privileges. Have attached the error message.

Is there a way to force delete via Terminal or mounted as a drive from a networked Mac? I have a few Macs on this network (both ethernet and wifi).

Macmini 2014 - 2.8GHz Intel Core i5, 8GB RAM, MacOS Mojave 10.14.6