parse error in /etc/sudoers near line

i miss modified /etc/sudoers and now below text out

/etc/sudoers: syntax error near line 31 <<<
sudo: parse error in /etc/sudoers near line 31
sudo: no valid sudoers sources found, quitting
sudo: unable to initialize policy plugin

I found server solution but not working.

example ‘pkexec visudo -f /etc/sudoers’

but just like below text not working

==== AUTHENTICATING FOR org.freedesktop.policykit.exec ===
Authentication is needed to run `/usr/sbin/visudo’ as the super user
Multiple identities can be used for authentication:

  1. ubuntu
  2. nvidia
    Choose identity to authenticate as (1-2): 1
    Password:
    polkit-agent-helper-1: error response to PolicyKit daemon: GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: No session for cookie
    ==== AUTHENTICATION FAILED ===
    Error executing command as another user: Not authorized

This incident has been reported.

I didn’t change nvidia’s passwd but not authorized .

why?

Dear sensewon,
Could you please check the difference in sudoers file w.r.t other Tegra and revert changes. If this does not fix please check flashing the board again