Okay, so I’m pretty decent at SWAT, but all of the sudden after winning one game I hit the super sweats and now I have a losing streak of 3, so the map “Truth” pops up and I think “no way am I playing this map, it sucks” (I wish I could visit 343 and force an update out that would remove truth) anyways, the map pops up and I close halo 5, open it back up and play a game, hardly 3-5 minutes in we have 4 kills the enemy team have 13, so I leave. Then I go tout matchmaking and the map truth pops up and again I think “no, I hate this map, please destroy it” and leave before anyone can join the session but when I come back to halo 5, it says I’ve been banned? Like I didn’t even start a game, and I only quit twice. Sorry if this is long, jusr needed to say this.
So in Halo 5 MM, Spartans are first joined together, and then the map is selected. By the time the map is chosen by the system, the groups are formed, and leaving MM becomes impossible by pressing B. Therefore, you are technically quitting. You say you left before anyone could join the session, but if you were in MM long enough for the map Truth to be selected, then the session had already been formed. So by leaving, your team would have been down a man. From your story, it sounds like you quit 3 times relatively close to one another, so a ban makes sense.
17 Dnf’s in the last month, the banhammer has a very long memory.
There’s a ban thread in Halo 5.