Go to your SourceBans site.
Admin Panel ->
Servers.
Click 'Edit' under the Action bar for each of your server(s), and adjust the IP address to match your server's public IP address.
Note the ID field near each server, you may need to set it in every single server in
addons/sourcemod/configs/sourcebans/sourcebans.cfg, like explained in the file:
Code:
// This is the ID of this server (Check in the admin panel -> servers to find the ID of this server)
"ServerID" "-1"
And done!