Before posting, please read how to report bug or request support effectively.
Bug reports without an attached log file are usually useless.
sudoers file. Typically in /etc/sudoers. As the FAQ says.
etc/ssh/sshd_config to PermitRootLogin without-password. I can login using scp and shell set to default without problem.
sudo su - I get this error in log. Therefore can't login as root and edit files. In terminal I can sudo with a problem.
Started a shell/command
. 2019-03-20 10:55:26.545 --------------------------------------------------------------------------
. 2019-03-20 10:55:26.545 Using SCP protocol.
. 2019-03-20 10:55:26.546 Doing startup conversation with host.
. 2019-03-20 10:55:26.599 Skipping host startup message (if any).
> 2019-03-20 10:55:26.599 echo "WinSCP: this is end-of-file:0"
! 2019-03-20 10:55:26.599 sudo: no tty present and no askpass program specified
. 2019-03-20 10:55:28.553 Server sent command exit status 1
. 2019-03-20 10:55:28.554 Disconnected: All channels closed
* 2019-03-20 10:55:28.614 (EFatal) **Connection has been unexpectedly closed.** Server sent command exit status 1.
* 2019-03-20 10:55:28.614 Error skipping startup message. Your shell is probably incompatible with the application (BASH is recommended).