BAD AND POOR SERVICE

I am not happy with the service that ABSA has been given me lately. I have used to much airtime calling back and forth regarding my change of direct debit order for my car payment but instead of changing it to the date we both agreed they still deduct it month end which is inconveniencing me, The worse part is that even after numerous phone calls I still get a bad service they will never get back to me regarding the issue I am disgusted I did not expect such from this well established bank, I would appreciate it if someone would clear it with me as why is my payment being deducted on the wrong date even thou I have changed it.