Changing of debit order without my approval

FNB, I do not appreciate you sending me to 4 different departments and you can’t answer a simple question as to why a debit order has been changed successfully without my approval. I don’t care if it’s coming from Nedbank or MFC, you are my banker and you should be able to answer my question as to what is happening with my account, and to the person that transferred me for the 5th time while I am speaking to you is so rude!