Postnet has not delivered my overnight package!!!!

My sister sent perfume to me via PostNet and I transfered money to her R180 to pay for overnight delivery, which was suppose to arrive yesterday at my work address, but nothing has come through and no one knows what's happening! I want my package as in yesterday!!!! I paid lots of money 4 overnight that didn't happen!<br> Lahliwe, the lady that assisted her said overnight!