Amazon Seller Duplicate Label

I ship out multiple boxes each day using USPS Ground Advantage and for the first time yesterday packages were being delivered too quickly for instance a package from Florida to California takes a few days and not under 15 hours and I had a package that was going to California but it got delivered to Texas. I called USPS and they told me that most likely the label got a duplicate from Amazon but how can this even happen I have had to refund so far 8 packages for the same problem since they were going to a different state for instance another package was supposed to go to MIssippi but somehow delivered to Maryland. I lost money and USPS said there’s nothing they can do about it.