Sorry, I thought you were insisting that it actually IS a tracking number, and I just didn't want to leave anyone with the impression that it is. USPS calls it that, but officially, straight from their mouths, it is just a delivery confirmation number, and they do not guarantee accurate tracking data. Our e-mails refer to it as a tracking number because that's what they call it on their website and we don't want people wasting time looking for the delivery confirmation entry field instead of the tracking number entry field, and because we use the same automatic e-mail form regardless of which shipper it is.