local MarketplaceService = game:GetService("MarketplaceService")
local Players = game:GetService("Players")
 
local productID = 0000000  -- Change this to your developer product ID
 
local function promptPurchase()
    local player = Players.LocalPlayer
    MarketplaceService:PromptProductPurchase(player, productID)
end

promptPurchase() -- Runs the Function