The U.S. Post Office is such a mess it is driving mail order services out of business. I am quitting selling books & paper patterns by mail---I sent a book December 15 and it arrived 60 days later. I will still sell PDFs in my Etsy shop.
Sorry, but I cannot afford to continue to replace missing merchandise and I'm tired of customers complaining about late deliveries. If you want to complain tell this incompetent holdover from the last incompetent administration: