Sometimes it's not the fault of the seller, sometimes Canada Post's system just sucks. I shipped a rifle out east and the tracking number was showing as invalid for about 3 days or so. I mean their tracking system didn't even recognize it even though it was the number printed on the receipt. I know the buyer wasn't at all happy considering he spent a good chunk of change, but there wasn't anything I could do since contacting Canada Post was useless. He pretty much just had to wait and see and trust that I wasn't scamming him. Eventually the tracking number worked and updated when it got scanned at one of their facilities en route to buyer's town. It was a weird situation. Perhaps you're on the receiving end of something similar?