Thanks for your reply.
I have allowed Local network access and created openvpn connection with strongvpn.com. Strongvpn has allocated me a static public IP with all ports open. I have tested their vpn on my laptop by using port listen tool to check the ports I need to be open and they are open. The Mango router activated the VPN, however for example SSH port 22
Name: SSH Protocl TCP/UDP External Zone: ovpn external port: 22 Internal Zone: LAN internal IP: 192.168.8.5 internal port: 22 status enabled

It doesnt work and it does open port 22. What I am trying to achieve is port forwarding to work when VPN connection is enabled and the device attach to the Mango router which is taking the static VPN IP accept incoming port connection.

In regards to the VPN provider they have allocated me static ip and all ports are open when the device listen to the port and a port scan is performed

Right now the Mango router is not working for portforward over vpn

Please assist