This means that the sender notified USPS on the 4th that he wanted to deliver the package by express delivery and paid the shipping fee. But the stuff doesn't have USPS. In other words, USPS only received a notification and did not receive the item. This is normal, because when sending USPS in the United States, all payments are made online. Once the order is paid, a tracking number is generated, but the items are not sent in a hurry. I usually send them after 1-2 days. If it is not sent, you can cancel the order number and get the shipping fee back.