The Post Office has been closing more processing centers which, I believe, is causing the problem. I was replacing but then the originals showed up. I'm telling my customers that it's taking longer and with the items that appear stuck or lost I'm contacting the Post Office and updating the customer. That's all you can do really. If at a certain point it does seem to be legitimately lost then the Post Office will reimburse you and you can refund or replace, whatever you and the customer decide on.