I placed an order recently. When I go to the Order History page, it shows the order but the tracking number is unavailable. Why?

I placed an order recently. When I go to the Order History page, it shows the order but the tracking number is unavailable. Why?

Please allow 3 business days for the tracking number to be updated on our web site. If three full days have passed, please contact us and we will inform you of the status of your order.