RainMaker

Hi, Hoping you guys can help me and my friend are trying to play online both from the same connection however the game will not load up when both of us try to join a match. If just one of us joins it works perfectly. Both of us have a different Port Set in Game Settings and this port has been forwarded on the router to each PC both have a static IP. We have tried with UPNP disabled and enabled no joy. Any ideas?