sudoers file problem with upgrade to 22.04

[Jack McGee]

I picked use package maintainers file on sudoers, probably should not have.


Now I do not have access to sudo.  Only one user on that machine that 
was upgraded, it can log in but has no access to sudo.


I have googled, and pkexec results in

mythuser at amethi:~$ pkexec visudo
Error checking for authorization org.freedesktop.policykit.exec: 
GDBus.Error:org.freedesktop.DBus.Error.NoReply: Message recipient 
disconnected from message bus without replying

** (process:7721): WARNING **: 12:21:16.111: Error unregistering 
authentication agent: 
GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name :1.99 
was not provided by any .service files

Same thing from terminal on machine.

If I go to recovery mode, pick drop to root shell, it asks for root 
password to continue.

Can this be repaired from bootable USB 22.04 stick?

How can I get into single user mode?  I have tried editing command to 
start ubuntu to no avail.  Fails.