Unable to start multiplayer match. Please try again

Hey guys, when me and my friend try to join eachother via Invite matches or Lobby matches, we get the error “Unable to start multiplayer match” even though we are from the same country, is there any way to fix this? Thanks in advance because we really want to play together. We both play on PC. I have checked the Teredo connection and everything is fine, on his end as well.