FTP Server DNAT

I have an internal FTP server that I want to have open to the Internet for file transfers.

1. Created a WAN interface with a public IP address.
2. Created a FTP Server with a private IP address.
3. Created a DNAT rule that allow
ANY > FTP service > WAN interface with Public IP > private IP address FTP server > FTP service

When I try to connect to the FTP server with the public IP I see the traffic in the Live Log, but the connection never happens. What am I missing?


Thanks,
JP