How to Fix User is Not in The Sudoers File Error - Ubuntu or Linux Mint

In this video I show you how to fix error "user is not in the sudoers file. This incident will be reported" This happens when trying to execute sudo that needs user escalation of privileges and the user has either been removed from the group or a setting is missing in the /etc/sudoers file. We take a look at how we can recover from this by booting in recovery mode