POOR SERVICE!

I upgraded Feb 2017 to a sim only deal with 2G data, 50 call minutes and 25 sms's. Two months after my upgrade I went back to our local Vodacom shop and asked if there was any way that I could increase my monthly minutes. He said yes and explained to me to take an additional 50 minutes for X amount extra. I did just that - he signed me up. From the end of THAT months I've been paying extra for 50 EXTRA minutes. I have NEVER received any extra minutes. NEVER! I have been at the vodacom shop twice to fix this!!! NOTHING CHANGED. I've called the service line Numerous times and my query gets escalated and escalated and in the rare occasion that somebody calls me back I must explain my whole story AGAIN and nothing happens!!!!! I'm very unhappy about the service. It's now the 10th month of me paying extra for something I've never received. If this is not sorted out very Quickly I will port both my numbers!