Cannot add SFTP destination


While adding SFTP destination, getting the following error:

sh: 1: --port: not found
Host XXX.XXX.XXX.XXX not found in /root/.ssh/known_hosts
can only concatenate str (not “NoneType”) to str [setupSSHKeys]

I checked known_hosts and it’s there, tried to clear it and fill manually - the system creates it’s own and renames mine as known_hosts.old

Could someone suggest what’s wrong here?