Frustrated with faulty invoice

I am so dissapointed with telkom mobile, I have taken out a contract for a phone as well as a rooter 10 gigabyte deal. When I recieved my invoice, the amount was much more than expected, I was invoiced for two rooter deals instead of one although I only recieved one and ordered one. I went to the store to try and sort it out but the que was very long and in the hour and a half that I was standing there the que didn't move even once. I then decided to call the call centre on Monday morning.... I was reffered from one department to the next several times, spending a great deal of my monday morning on the phone, i finally logged a dispute and my case number was given to me. They ensured me that this will be attended to within 72 hours, it's been 5 days now and the invoice has already been deducted from my bank account an nobody has contacted me in this regard. I will probably have to spend more time now calling the call centre. This is really poor service in my opinion!