Incorrect Billing from July 2014 not rectified

I've spoken to your accounts department numerous times regarding the incorrect charge billed to me in July 2014, to be told that it will be reversed. It's been 6 months and nothing has been done about it. <br> I do understand that 29000 people were billed incorrectly and that it will take time to rectify but 6 months? Furthermore, when the error is on your side, why do us, the consumer, have to be faced with threatening messages on our statement? The fault is not on MY side - the monthly charges are paid every month without fail. The fault is on YOUR billing system. I would like a reply from a senior person in the accounts department to give me a reply as to when this will be resolved. Please do not tell me to go in to a service centre to rectify this - neither me or my husband has the time to do it, neither do I want to talk to any of the staff for them to tell me to be patient and wait for it to be corrected. '