Postal Locations

I have never ever had a problem with the USPS. In fact, every xmas, I tip my Mailperson. This office, is the WORST customer service I have ever experienced. On April 14, 2016, I sent my niece, some invaluable clothes, in a big grey bubble envelope, that she needed for her see design class at UCLA, that I had promised her. I went to the USPS, and they said, 15.00 postage, regular mail, was fine, as it was going from San Diego to LA. My niece never received the package, and people have told me they would look right into this and get back to me (Mr. Merlo Mendoza) and never have. No one can answer my question, that if the package was undeliverable FOR ANY REASON, it goes back to the sender. Every mail person, has confirmed that also. Not rocket science. I have not gotten the package and no one can tell me where the package is. One lady called me, and said she would find out who delivered the mail to Maple street that week, and I've never heard from her. Today, I spoke to Ron, who I was on hold, waiting for, for 24 min, and when i started to explain my issue, he HUNG UP ON ME. This is the most inept, rude, bunch of people who DONT CARE, hate people, and hate their job. Not my problem. I want to know where that package is and why I did not get it back, and I'm not going to give up. We must be accountable to USPS, by not sending certain things, and they must be accountable, for loosing, a very valuable package, that I paid them 15.oo to deliver, and they did not deliver it. And they are obligated to tell me why, it was not properly , sent back to me, which is procedure.