United States Postal Service lies to me

In response to a complaint that our mail was not held as requested while we were out of town, I received this reply from the United States Post Office just a few minutes after submitting my complaint:

I am sorry your mail was not held, I assure you we do try to hold everything we receive notice for. The carrier says he did not receive a notice and our system is not perfect. I hope you did get all of your mail.

Our mail carrier is not a he. She's a she.