Does your order status say, "Shipment Received, Package Acceptance Pending?"
This means that the USPS driver has picked up your package and is on its way to the sorting facility. There may be a delay as each package must be manually scanned when it arrives at the sorting facility. Once your order has been scanned it will then be sorted by destination and be on its way soon. Ultimately, this notification means that the package has taken its first step necessary to be delivered to you.
If your package has been at this step for more than several days, rest assured that your package is still making its way to you. Usually, it takes around 1 to 5 days for this step to be completed.
Your package may also be on its way to the next sorting facility but was not properly scanned after being accepted for transit. When it arrives at the next sorting facility, your tracking information may update. However, we are seeing a lot of tracking information stuck at the 'Acceptance Pending' phase until the package is ready for delivery. At which time, you will finally receive a new tracking update informing you of this.
If it has been more than 15 days, it is time to reach out directly to the USPS Customer Care department to inquire about your package's status.