Why PromptProductPurchase Isn't working?

Hello, I made an product script for an donate gui, I tried to buy my product but there was an error. What is the error in my script? I think i am true but,

local Player = game:GetService("Players").LocalPlayer
local MarketplaceService = game:GetService("MarketplaceService")

for _, thing in pairs(script.Parent:GetChildren()) do
	if thing.ClassName == "TextButton" then
		thing.MouseButton1Click:Connect(function()
			MarketplaceService:PromptProductPurchase(Player, thing.ID.Value)
		end)
	end
end

Try to make pairs in a function That helps me

local Player = game:GetService("Players").LocalPlayer
local MarketplaceService = game:GetService("MarketplaceService")

function press_btn() -- Creates a function
    for _, thing in pairs(script.Parent:GetChildren()) do
        if thing.ClassName == "TextButton" then
            thing.MouseButton1Click:Connect(function()
                MarketplaceService:PromptProductPurchase(Player, thing.ID.Value)
            end)
        end
    end
end

press_btn() -- Starts a function