In order to make the port forward work it's necessary to make sure that the router has a public external (WAN) IP address. Please double check if router WAN IP address falls in the range within any of the following addresses:
10.0.0.1 - 10.255.255.254
100.64.0.1 - 100.127.255.254
172.16.0.1 - 172.31.255.254
192.168.0.1 - 192.168.255.254
If this is indeed the case, then this means that the WAN IP is a private IP address. In this case, it is a must to get an external public IP address from ISP or, if there is no way to obtain an external public IP address, please refer to this guide for private WAN IP solution using VPS.