You must have some weird nag issue if you can't get into a game after two weeks. On sky fibre here and can drop into a halo anniversary game in 2 mins.
I dont think its a regional problem, but the issue is real and not connection related. Me and a bunch of other people are having the same issue.
-Open Nat
-Can play every single game just fine (even Halo 5 Beta when was open)
-Some updates ago I was able to find matches between 2 or 3 minutes.
But now, when I search for a match in Halo MCC, I get stuck at "searching for players..."
If a friend of mine that can find matches put me in his group however, then I can find matches with him. Playing alone its impossible though.