Bad ssh config on remote server. Cannot login in

To resolve this issue you have to commented out line 55 in /etc/ssh/ssh_config

#PermitRootLogin yes

PermitRootLogin is actually an option which is valid in the /etc/ssh/sshd_config file; not the ssh_config file. The difference is that the sshd_config file controls the SSH server and the ssh_config file controls the client. Therefore, it would indeed be a bad (invalid) config option in the client settings file.

You do not need to do it remotely! Just delete permitrootlogin line from local /etc/ssh/ssh_config file which used during ssh connection to a remote server.