How do I make a chatted when someone says ;kill PLAYER, player dies?

I tried this:

function findPlayer(name)
    for _, player in ipairs(game.Players:GetPlayers()) do
        if player.Name:lower() == name:lower() then
            return player
        end
    end
end

game.Players.PlayerAdded:connect(function(plr)
    plr.Chatted:connect(function(msg)
        if msg:sub(1,5) == ";kill" then
            victim = findPlayer(msg:sub(7))
            if victim and victim.Character then
                victim.Character:BreakJoints()
            end
        end
    end)
end)

but I always get a error saying