CELL C is USELESS

After I complained on this site, I had a call from Cell promising to credit my account with R 1,700 as there was a mistake on the data usage and they promised that it will appear on my next statement. So the statement arrived and no credit was given. I emailed Jane Mbatha and asked what is happening. This happened on 16/03/2015 when I e-mailed her. Today 23/03/2015 I get a call from the credit department asking when I am going to pay. I asked her if she can see any notes made on my account regarding the credit that is due, but there was nothing. I once again e-mailed Jane and have had no response. They make you an exclusive customer and promise that you will get the best service. Ever since I joined, I have had nothing but bad service from Cell C. Why are you not correcting the accounts after you have admitted that you were wrong? Do you just expect people to forget and pay whatever is on their account. Is doesn't work like that!! Stop robbing us!!!!!! They keep phoning me on the wrong number and don't even bother reading e-mails where I state the correct number to use