Multiplayer still not working.

When I first bought the ultimate edition of forza 6 I couldn’t wait to play. I could at least play some multiplayer but in the last two weeks I have not been able to join a lobby. I’m frustrated by it and have tried lots of things. I know it’s not my multiplayer connection as its fine even all my other games work well. My nat type is already open. I have hard reset the console. What changed that things now don’t work? I have messaged for support but haven’t heard anything back. I looked at the Xbox live servers and they seemed OK to me.sorry I’m not a tech expert. Can you please help. Thank you