United States Postal Service [USPS]

I've been complaining for over 1 year about this post lady that doesn't like delivering packages because I live in a big building. I live on the ground floor and every time I order something she leaves a receipt for me to pick it up! It's been over 1 year and she is still doing the same thing and I've gone to the post office and complained and over the phone. How can I get help with this? The packages are not heavy either. She's old and is in a bad mood all the time especially when she has packages. All she has to do is call me on the intercom and I will come out and get it. She doesn't do that and instead writes a receipt for me to pick it up. Why hasn't the post office fixed this situation and I'm not the only one complaining in my building but she tells the other tenants that she is not allowed to deliver big packages and that's ridiculous. When she is off the other post lady comes right to my door and gives me my packages! Why doesn't the post office do something about this situation and tell the post lady to do her job? For 1 year I've been complaining but I guess the customers are not important.