I have done port forwarding. Also tried vpnstein.
Vpnstein version 3 is getting installed..so they are asking for username password. I have also set static ip for the same purpose

Network diagnostics details
Starting networking diagnostics...

Your local network port (UDP) is 16000. All game traffic is routed through this port. This can be changed in "Settings" -> "NAT Traversal".

Attempting to connect to 3 test servers. This will take around a minute to complete...

Received data from 'server 3' through port 37305 (this is your WAN or router port)
Received data from 'server 2' through port 16746 (this is your WAN or router port)
Received data from 'server 1' through port 63255 (this is your WAN or router port)
14 seconds left.
9 seconds left.
4 seconds left.

Test Result: Symmetric NAT
Network Health: Poor
Recommended Action: Port forwarding recommended or switch routers. The only port you need to forward is UDP port 16000 on Voobly you do NOT need the direct play ports 2300-2400 and 47624.
Details: Your router assigned different public ports to all the test servers this will make it hard for users to directly connect to you. You will likely see a large number of fast proxies.