Connection Interrupted

Hello, I have been trying to play Halo Reach through matchmaking on Steam MCC, but for whatever reason when I load into game I am instantly disconnected with the popup saying “Connection interrupted.” followed by a temporary ban for disconnecting too early. I have only had this issue for Reach and not Combat Evolved, but always consistently disconnect when either in match or loading in. I have checked my internet connection speeds to find that it is completely stable which any help would be appreciated.

They have yet to mention or fix this problem. I haven’t played CE in a while but to this day I cannot load into a match of Halo Reach. No matter the playlist, I get the same message. Internet is fine and I have an open NAT type, relays are off, and I have reinstalled the game on steam 5+ times to try and fix this issue.