Halowars 2 server disconnect

Hi I bought halo wars 2 on pre release started the game well was enjoying the online and then I got disconnected from the halo wars online servers and could never get back online tried for a few weeks and nothing in the end I gave up, then 2 weeks ago a friend of mine ask me to reinstall it and play it with him thinking surely an update must of been available in the last 2 years it would be up and running fine. I downloaded it and it connected then 5 seconds later disconnect and repeats all the time iv uninstalled the game unplugged the Xbox hard reset Xbox cleared the cache on Xbox iv tried everything and still can’t have a game of halo wars 2, my nat type is also open what should I do ?