Billed incorrectly for 3 month consecutive months

I called Telkom on the 04.12.15 , advising I was still being billed for the previous data pack. The agent said the was a technical problems in November and my account will be credited on my next billing. I requested a new statement but the agent was unable to provide 1. The reference number given - ***3. Again I was billed the incorrect amount. I called Telkom again on 07.01.16. The agent was not able to pick up the reference and I had to repeat my issued, waited 15 +- mins for the agent to gather info, I was advised they will send a message to the technical department to remove the data package and another request for a credit was sent. New Reference no. given ***2. On 27.01.16 I received a message on my phone advising my account will be debit 441.96 ( which includes the data pack). Called telkom again, repeated my story. I tried answering calls from Telkom on 31.01.16. I didn't have enough time to remove my cellphone from my bag before they cut the calls. I called Telkom again on the 01.02.16. Again repeated my story. Zuma stated the system reflects a credit but was still not done. She sent a message to Zanele in the back office for more info.