Can't remove a VPN Network Service

I have an old VPN profile that I can't delete. I have seen previous queries about this that have recommended use of the following commands:

1. In Terminal: networksetup -listallnetworkservices
2. In Terminal: networksetup -removenetworkservicenetworkservice

I have two locations defined and the VPN is listed using the command above for only one of them. If I set the location to the one that does return the VPN, the remove fails with the message "You cannot remove myVPNName because there aren't any other network services on IPv4".

There are other suggestions for removing it:

1) Editing the system preferences plist to remove the network service. Under Catalina I don't seem to be able to do that due to the read-only arrangement for system files.

2) Deleting the VPN under the Profiles tab in the system preferences. I know there used to be a Profiles tab, however it is no longer there. That had been added by Microsoft Company Portal, and may have been removed when I deregistered my computer.

Any ideas that might help?