bad customer service

I bank with Standard Bank and have taken credit with the bank. I also have a bond with Standard. Some months ago I changed my debit order for the bond. For some strange reason you need to also to inform the Personal Lending team of the same information. Last month I sent an email to Personal Lending informing them to change the debit order from 23 to 30. This email was acknowledged and a promise made to act on the request. This however has not bee done as this month the order has again gone off on 21 April. What is the use of email communications if they are not acted on? I am really disappointed.