still billing me incorrectly

Hi Guys, I am still being billed for 4mb ADSL line when it should be 2 mb as per my other disputes logged and faults and account changes, I dont understand how you are still billing me incorrectly! ADSL Line Speed Cost Difference R134 x 4 Months R536, uncapped data difference R57 x 4 Months R228.<br> <br> Total Amount: R764<br> <br> Please can you credit this amount on my account, I have not been paying the different and now the account is in arrears please correct this going forward otherwise I am just going to keep logging disputes. <br> <br> Thank you<br> <br>