No problem Mohamed...after I posted that, I did reach back out to him for step by step...and he said he just simply logged into his account, went to the product page, dropped it into his cart, hit checkout, and paid with PayPal. That was it.
I couldn't replicate it either...so I am guessing it was just a temporary issue with USPS. Everything completed properly, no errors on the invoice for shipping, and the PayPal process completed properly as well.
So I guess we can just call this a non-issue unless it comes up again.
Thank you very much for looking into it. I really appreciate it.