This Admin Command isn't working. Help?

So here's what I have...

char = game.Players.LocalPlayer.Character
plr = game.Players.LocalPlayer
local admins = {"DDDropTheBase"}
 
function tableContains(t, value)
    for _, v in pairs(t) do
        if v == value then 
            return true
        end
    end
    return false
end




-- Blockhead Command
if string.sub(msg,1,5) == "blockhead " then
local player = game.Players:FindFirstChild(string.sub(msg,6))
if player then
char.Head.Mesh = nil
end
end

The blockhead command doesn't work, when I say "blockhead dddropthebase" Nothing happens.

Characters 1-5 would not contain "blockhead "

You obviously did not write this yourself, but that is the error.

Could you still help me? I want it where you say "blockhead name" it makes their head a block. And I need a different Admins Table, because when I do that, all of ROBLOX's commands come up, I want my own command.