Power hour disappears within minutes

I bought 180 minutes for 3 days and without even using all the minutes my phone said that i have no more airtime. I checked the calls I made and they did not amount to 60 minutes for the day. I then called vodacom and spoke to Busy at 18h52 who was very rude and kept quiet on the phone with the hope that I will drop the call. She told me to count the minutes of which is her job and when I tried to explain to her that i have already counted the minutes she raised her voice at me interrupting me when I speak.