Help with developer products?

so, i have a script to buy a color for my sword, but the problem is, when you buy it, it doesnt give you the color and just take your robux. here the code

local MarketplaceService = game:GetService("MarketplaceService")


MarketplaceService.ProcessReceipt = function(purchaseInfo)
    local player = game:getService("Players"):GetPlayerByUserId(purchaseInfo.PlayerId)
    if purchaseInfo.ProductId == 974191894 then
    local TakeNumber = {7,6,5,4,3,2,1}
    local ColorPicked = math.random(1, #TakeNumber)
    local save = player:WaitForChild("ColorsSave"):WaitForChild("Colors"):WaitForChild("Color")
    if ColorPicked == 7 then
            save.Value = 7
            player.Character.Sword.Sword.Katana.MeshPart3.BrickColor = BrickColor.new("Black")

elseif ColorPicked == 6 then
            save.Value = 6
            player.Character.Sword.Sword.Katana.MeshPart3.BrickColor = BrickColor.new("Light stone grey")

elseif ColorPicked == 5 then
            save.Value = 5
            player.Character.Sword.Sword.Katana.MeshPart3.BrickColor = BrickColor.new("Lily white")

elseif ColorPicked == 4 then
            save.Value = 4
            player.Character.Sword.Sword.Katana.MeshPart3.BrickColor = BrickColor.new("Mid gray")

elseif ColorPicked == 3 then
            save.Value = 3
            player.Character.Sword.Sword.Katana.MeshPart3.BrickColor = BrickColor.new("Hurricane grey")

elseif ColorPicked == 2 then 
            save.Value = 2
            player.Character.Sword.Sword.Katana.MeshPart3.BrickColor = BrickColor.new("Cloudy grey")

elseif ColorPicked == 1 then
            save.Value = 1
            player.Character.Sword.Sword.Katana.MeshPart3.BrickColor = BrickColor.new("Really black")
        end
        return Enum.ProductPurchaseDecision.PurchaseGranted
end
end