INcompetency at Standard bank

I have a home loan with STD and they have been debiting my account on the 28 of every month last month they debited on the 25 God knows who told them to do that, and I had to pay charges and the money bounced back. Eventually they debited same month on the 28th This month they debited on the 25 th again it it bounced back again and I have to bay the charge all the time it bounced back. I called this Monday and told them to debited on the 28th.. and I was told they didn’t get the money for last month I told them to deduct for both month(last month and this months) Yesterday they debuted only for one month and this morning they have debited again for both months in order words they have debited three payments today and yesterday. I’m left with nothing on my account and when are people that I’m owing try to debited it’s going to bounce back. Standard is becoming a nightmare these days and I have been their client for 20+years in thinking of doing my business somewhere else and their call centre agent drop the phone on my ear when I was telling them how *********** are after I was holding for 30.mins she decided to hung up on me.