edit file sudoers
sudo nano /etc/sudoers or sudo visudo
%sudo ALL=(ALL) ALL
%sudo ALL=(ALL) NOPASSWD: ALL
and add following line to the end of the file:
user ALL=NOPASSWD: ALL
When editing sudoers, it’s necessary to be very careful. Any error cause that you will not be able to edit this file anymore and also not to use sudo ;-).
Here are links how to fix it (verified 😉 )