Developer Product purchase prompt appears in studio but not in game?

In studio, this code prompts me to purchase the developer product, but in game it does not. Help!

local plr = script.Parent.Parent.Parent.Parent.Parent
local link = game:GetService("MarketplaceService")

script.Parent.MouseButton1Click:Connect(function()
local marketId = 325595311  
link:PromptProductPurchase(plr,marketId)
link.ProcessReceipt = function(receiptInfo)
if Enum.ProductPurchaseDecision.PurchaseGranted and receiptInfo.PlayerId == plr.userId then
plr.leaderstats.Ticket.Value = 2 
wait(1)
end
end
end)