How can I make a GUI appear after a dev product is bought

I have a “Help” dev product that when bought should show a GUI which provides a clue to the user. How can I add a script to the GUI so that when the product it bought, the GUI becomes visible. Thanks

take a look at this callback: MarketplaceService.ProcessReceipt (roblox.com)

Hm I don’t really understand what do you want could you explain me detailed all I understood is: when you bought a product a gui disppears

Not what he is even aiming for, hes aiming to make the gui appear WHEN the dev product is been brought.

This script should help.

local MarketplaceService = game:GetService("MarketplaceService")
local Players = game:GetService("Players")
local rs = game:GetService("ReplicatedStorage")
local productFunctions = {}

productFunctions[1330168572] = function(receipt, player)
        gui.parent = player.Playergui --do something with the gui here
	return true
end

local function processReceipt(receiptInfo)
	local userId = receiptInfo.PlayerId
	local productId = receiptInfo.ProductId

	local player = Players:GetPlayerByUserId(userId)
	if player then
		-- Get the handler function associated with the product ID and attempt to run it
		local handler = productFunctions[productId]
		local success, result = pcall(handler, receiptInfo, player)
		if success then
			-- The player has received their benefits!
			-- return PurchaseGranted to confirm the transaction.
			return Enum.ProductPurchaseDecision.PurchaseGranted
		else
			warn("Failed to process receipt:", receiptInfo, result)
		end
	end

	-- the player's benefits couldn't be awarded.
	-- return NotProcessedYet to try again next time the player joins.
	return Enum.ProductPurchaseDecision.NotProcessedYet
end

-- Set the callback; this can only be done once by one script on the server!
MarketplaceService.ProcessReceipt = processReceipt

try researching and play around with is next time

(I’m quite sorry for the bump but it’s just to solve the issue.)

Firstly, create a new game.
Secondly, go to Monetization and create a product.
Thirdly, do this script:

local ID = "Your ID here!"
local MarketplaceService = game:GetService("MarketplaceService")
task.wait(-math.huge) -- It's negative infinity (-inf).
local GUI = game.StarterGui["Your GUI Name here!"]
GUI.Enabled = false

script.Parent.MouseButton1Click:Connect(function()
	MarketplaceService:PromptProductPurchase(game.Players.LocalPlayer, ID)
	GUI.Enabled = true
end)

They’re asking after the dev product is been bought so We should assume they’ve already done this