Cannot connect to sftp server by public IP

Question

I'm trying to configure SFTP server on my laptop with freeSSHd and freeFTPd. I have no problem to connect by private IP address (tested with WinSCP). The problem comes when I'm trying to connect by public IP - message is "Searching for host" and then after few seconds "Network error. Timeout".

• I configure router's port forwarding on port 22 to my local IP with TCP protocol
• SFTP server is running (Listen address: myprivateIP, port: 22)
• SSH server is running (Listen address: myprivateIP, port: 22)
• I set inbound rule in firewall on port 22
• I tried turn off firewall for test
• I have static IP on my laptop

What could be the reason of no connection by public address? Thanks for help.