The "PORT" command is part of the Active FTP mode connection and it requires the FTP Client (CA WA System Agent / FTP job) to share its IP Address to the external FTP Server. It is probably that the CA WA Agent is sharing its local address (intranet) with the FTP server, but connects using its external IP address (***.xx.***.250) and FTP server does not like the mismatch (external vs local).