Local by Flywheel Settings
Quit Local if it's running
Go to ~/Library/Application Support/
by opening Finder and pressing Command+Shift+G and then remove Local by Flywheel
(assuming you don't have any blueprints or sites)
Open VirtualBox.app
in /Applications
and power off and remove the local-by-flywheel machine
Re-open Local by Flywheel
and attempt installation again