Failed to connect to a network game (Farming Simulator 15)

Hello. I bought 2 of the license, Farming Simulator 15 and encountered a problem: my friend who lives me 100 km, cannot connect through steam to my created game. I've sat around on the Internet and look for the answer to this question. I conducted an experiment: connect 2 computer to the next is not present, create the game and it comes on and runs everything. (Use the same accounts for Stimul that and a sidekick.) And that is why at no great distance, we cannot connect to each other??? Maybe someone faced similar problem?