Staff don't know how to change a debit order date.

I requested that the Discovery Bank staff change my debit order date to the last day of the month as I recently started a new job and I only get paid on th last day of the month instead of on the 27th day at my previous job. The staff of Discovery messed the date up many, many times. I have had to pay penalties because of their incompetence, I have also had to waste my time and airtime phoning Discovery over and over in the hopes that they would finally get it right. They are completely useless. I have been a Discovery card holder for more than 5 years and they only Time I paid late (both times) is because these idiots don't know how to change a debit order date!