Surface Gui Shop?

Can anyone tell me what wrong with this script.

Player=script.Parent.Parent.Parent.Parent.Parent
script.Parent.Text=tostring(script.Parent.ItemName.Value)..": "..tonumber(script.Parent.Cost.Value).." "..tostring(script.Parent.Currency.Value)
script.Parent.MouseButtom1Click:connect(function()
if Player:findFirstChild("leaderstats") then
if Player.leaderstats[script.Parent.Currency.Value].Value>=tonumber(script.Parent.Cost.Value) then
Player.leaderstats[script.Parent.Currency.Value].Value=Player.leaderstats[script.Parent.Currency.Value].Value-tonumber(script.Parent.Cost.Value)
game.Lighting[script.Parent.ItemName.Value]:Clone().Parent=Player.Backpack
game.Lighting[script.Parent.ItemName.Value]:Clone().Parent=Player.StarterGear
end
end
end)

The script is inside a Textbuttom which is inside a frame which is inside a SurfaceGui