Multiplayer PVE connection issue (at least in group)

So what title said. I & my gf connecting from one router. Until ~35 lvl it was okay but now… Well, now we can’t connect together in closed pve games. Pvp works perfect. I tried solo pve (prologue), it loads without any problem and than again in party – same, 30 seconds in starting for game, after it 1:06 min timer for me and I can’t connect to server. What we tried: 'till her pc is okay, mine was: rebooted, flushed dns service, rechecked game files (100% okay). I also rebooted network router, re-up wifi connection settings. Still have this issue.
Any ideas?