Unhappy

I went into a Telkom mobile shop in MIDRAND to migrate my wifi package from a 10+10 to a 30+30. Upon inquiry I was informed that it will cost me R400. I was happy with that and I asked the lady to go ahead. So ahead she went. That was in November 2015. End of December I was billed R4132, to which I was shocked. Yet I went to Telkom to inquire. I was told that their head office often do that. It was explained to me that the assumption at their head office was that I had taken a new device/ router upon migration which wasn't the case. I reversed the debit order and paid the difference of R1088 and logged a complaint which was confirmed via sms. The most frustrating thing to me is that I can't really get any feedback and yesterday I was again debited R1500. Am not a happy chappy because that reflects badly on me at my bank since I have to reverse that debit order again and also the fact that on my itc it may reflect that I didn't pay a full amount. I would like someone to call me and tell me what is going on since their call Centre agents can't really help. I would like this to be resolved asap. It's frustrating when you can get answers over matters of this nature.