Problem with kaillera client

So when my friend tries to join p2p after entering my op address and port 27888 he is in an endless connect loop that doesn’t connect to my server. I tried to connect to him as a host but same deal. We then tried server browser on client and while we were able to connect to a lobby together with me as host, after pressing start it says all players are ready and then Nothing happens. Is there something I’m missing? When I exit out after starting it says the client gets shut down and I have to boot it up again