What Is Wrong With This Sword Shop Gui?

When I click to buy the speed coil it doesn't give it to me. Whats wrong?

player = script.Parent.Parent.Parent.Parent.Parent -- your backpack
Points = player.leaderstats.Knockouts -- type of currency used (EX: Money, Cash, Gold, Points)
upgradeStuff = script.Parent.SpeedCoil -- The name of the tool, put it in this button's parent

function buy()
if Points.Value >= 8 then -- Change the 100 to the price you want

    Points.Value = Points.Value - 0 --  same as above

        upgradeStuff:clone().Parent = player.Backpack -- puts the item into the backpack

    wait(2)
else -- if you don't have enough money
        script.Parent.Text = "Not Enough Funds" 
    wait(3)
        script.Parent.Text = "Speed Coil"  -- change WeaponName to your button's text
end
end

script.Parent.MouseButton1Down:connect(buy)