As I ship via registered mail, my packages will need signatures to be received, either by family members or the recipient themselves. When the package is undelivered the postman will bring it back to the post office. And if not claimed for one month, it will be kicked back to the return address. Which is what happened here.
I already contacted the buyer and she said she did not find any notices. I've heard a lot of stories like these about USPS's services - lazy to go up some stairs to deliver a package, so left notice to neighbor below who probably tossed it. Claimed they left a notice but didn't etc. It's frustrating really, since it probably ended up with a package being kicked back to where it came from and I need to send it again.
So had you had any bad experiences with USPS before? This is your chance to rant. :P