You can't just be banned for chat out of the blue, you get warnings first, then restrictions and than a time limited ban, you can't be banned from competitive out of the blue because of chat.
https://www.dailyesports.gg/valorant-patch-adds-escalated-penalties-for-chat-based-offenses/
"First, a player will receive a warning about their report in effort to encourage the offense to not happen again. Then, the player will receive queue restrictions. This makes them unable to queue for a certain time. Experience point denial is the next step. With this, the player will not receive the full amount of XP for a game. Next, Valorant will ban them from the competitive queue. Finally, the player will be entirely banned from the game for an undisclosed amount of time."