How can I fix this developer product script? [closed]

I'm making a tycoon and I want to make dev products to help with speed, cash, and health. Here's what I did.

game.StarterGui.ResetPlayerGuiOnSpawn = false old_fog = game.Lighting.FogStart local MarketplaceService = game:GetService("MarketplaceService")

function getPlayerFromId(id) for i,v in pairs(game.Players:GetChildren()) do if v.userId == id then return v end end return nil end

MarketplaceService.ProcessReceipt = function(receiptInfo) local productId = receiptInfo.ProductId local playerId = receiptInfo.PlayerId local player = getPlayerFromId(playerId) local productName

-- Down below is an example of a Cash boost

-------------------------------------------------------------------

if productId == 310891759 then
    local cashmoney = game.ServerStorage.PlayerMoney:FindFirstChild(player.Name)
        if cashmoney then
            cashmoney.Value = cashmoney.Value + 50000
        end



    elseif productId == 310891034 then
    local cashmoney = game.ServerStorage.PlayerMoney:FindFirstChild(player.Name)
        if cashmoney then
            cashmoney.Value = cashmoney.Value + 100000
        end
    -------------------------------------------------------------------

    -- Down below is an example of a Health boost

    -------------------------------------------------------------------

    elseif productId == 310891759 then
    local char = player.Character
    char.Humanoid.MaxHealth = char.Humanoid.MaxHealth + 20
    wait()
    char.Humanoid.Health = char.Humanoid.MaxHealth
    -------------------------------------------------------------------

    -- Down below is an example of a WalkSpeed boost

    -------------------------------------------------------------------
    elseif productId == 310892411 then
    local char = player.Character
    if char then
        local human = char:FindFirstChild("Humanoid")
        if human then
            human.WalkSpeed = human.WalkSpeed + 5
        end
    end



    elseif productId == 310892160 then
    local char = player.Character
    if char then
        local human = char:FindFirstChild("Humanoid")
        if human then
            human.WalkSpeed = human.WalkSpeed + 10
        end
    end
    -------------------------------------------------------------------

    -- Down below is an example of a gear giver

    -------------------------------------------------------------------

    elseif productId == 310892411 then
    game.ServerStorage.GodlySword:Clone().Parent=player.Backpack

    -------------------------------------------------------------------
end
return Enum.ProductPurchaseDecision.PurchaseGranted     

end

But when I do a test purchase, it doesn't work. Help?