How to make a button disappear for a certain player?

I am making a shop (button) which will be invisible for certain players who enter the game. However, when I was testing it (I was one of the certain players), the button was still there on my screen. I have no idea what mistakes occured in the script. Can someone teach me how to fix it, please?

Below is my script:

--Should the script be a local script or normal script?

local button = script.Parent
local player = game.Players.LocalPlayer

game.Players.PlayerAdded:connect(function()
	local admin = ( --The players who have one of the UserIds below should not see the button.
		player.UserId == 90568658 or 
		player.UserId == 76204529
	)
	if admin then
		script.Parent.Visible = false
	else
		script.Parent.Visible = true
	end	
end)

Try. (P.S. Local)

local button = script.Parent
local player = game.Players.LocalPlayer

game.Players.PlayerAdded:connect(function()
    local admin = {--The players who have one of the UserIds below should not see the button.
     	["90568658"] = true;
        ["76204529"] = true
   }
    if player.UserID[admin] then
        script.Parent.Visible = false
    else
        script.Parent.Visible = true
    end 
end)