Wrong Billing on my account, November and December

Telkom Billed me more money in November and December months last year, and I logged a call for them to payback my money. When I ask to speak to Manager I was told she is very busy or to speak to credit controller department they told me they don't have they contact details.<br> <br> I have a contract with Telkom form 2010 until today I never experience this issue for wrong billing when I upgrade my cellphone<br> <br> <br> Below is all my call that I logged and told different story. Ref ***9, ***2,***6<br> <br>