Why have i been banned for unsportsmanlike conduct?

I was banned for this game here https://www.faceit.com/en/cs2/room/1-7ddec2e6-53f7-4c7a-9a54-280b8ab06306/scoreboard and i simply do not understand why. I said 1 thing in the all chat which was "rat" and that was it. I didn't say much in the chat to the team, other than "purple went to donut and a instead of holding mid" followed by "it is what it is". I do not understand what i've done??