Me and my friend wanted to play Far Cry 4 together for a very long time. Now we both finally bought Far Cry 4. I have Far Cry 4 on Uplay and my friend has it on Steam. He has his steam account linked with Uplay. The problem is that we can't join Co-op neither can we play Co-op together. When one of us try to join another, this error shows up "Cannot connect to a game session". What should we do?