Inconsistent and poor service

For close to 10 years I have been paying my bond directly - not through debit order. Today I received an sms from Standard Bank saying that my debit order did not go through. I called the contact centre and as the line was bad, the consultant promised to call me back. No one called. I then called again and after being on hold for over 20 minutes whilst the consultant was checking, I was told to write a letter to the bank indicating that I do not want a debit order. I had previously done this and this is why I have bene paying like this for nearly 10 years. Why should I do this now!!