Why isn't my purchase script adding to leaderstats?

Hello!

I have re-written my script a bit and am still have issues w/it working. I am trying to add +1 to the customers leaderstat any time they purchase a clothing item from my home store, I have this as a server script:

local mps = game:GetService("MarketplaceService")

mps.ProcessReceipt = function(receiptInfo)
   local Player = game.Players:GetPlayerByUserId(receiptInfo.PlayerId)
   if receiptInfo.ProductId == 1234546 then
        Player.leaderstats.Purchases.Value = Player.leaderstats.Purchases.Value + 1
        return Enum.ProductPurchaseDecision.PurchaseGranted
   elseif receiptInfo.ProductId == 12345467 then
        Player.leaderstats.Purchases.Value = Player.leaderstats.Purchases.Value + 1
        return Enum.ProductPurchaseDecision.PurchaseGranted
  
   end
end

I used "123456" and "1234567" as placeholders, I would put the actual ID of the item there in game.

I have a basic leaderstat script:

game.Players.PlayerAdded:Connect(function(plr)
    local Stats = Instance.new('Folder') 
    Stats.Name = 'leaderstats'
    Stats.Parent = plr

    local Purchases = Instance.new('IntValue')
    Purchases.Name = 'Purchases'
    Purchases.Value = 0
    Purchases.Parent = Stats


end)

Any suggestions or thoughts as to why this is not working?

ProcessReceipt only works with Developer Products.