In order to publish a website for your main domain via FTP use the following details:
Publishing
Site name: leave it blank
FTP Server Settings
Server address: server your account is hosted on
User name: your cPanel username
Password: your cPanel password
Directory/Path: public_html/
Protocol: SFTP
Port: 21098
Website URL
URL: http://maindomain.com 
To publish a website for your addon domain via FTP use the following details:
Publishing
Site name: folder for your addon in home (by default, it is addondomain.com)
FTP Server Settings
Server address: server your account is hosted on
User name: your cPanel username
Password: your cPanel password
Directory/Path: addondomain.com/
Protocol: SFTP
Port: 21098
Website URL
URL: http://addondomain.com 
That's it!
Need any help? Contact our HelpDesk