bad service

I have an existing loan account with the bank,unfortunately i was retrenched in december,so i fell behind wth my payments.I got a job this august,so i called the collection dept. 2 arrange payment.I spoke to a consultant(i dont remember his name),i told him that due to the training stipend am recieving each week(which is R1080),i can only manage 2 pay R150 per week till end of october then after training i can make proper arrangements as il b earning more.But ever since i made the arrangement i am being debited thrice that amount!!! I went to the bank,the money was reversed(this happened a week ago as well,i called the call centre(on the 3rd september ,at 17:20),got through an agent with a bad attitude,who called her team leader on the line(Sibonelo was the name he gave me),he apologised and stated that he has made proper arrangement,that going onwards id be debited the R150,but i see again this week i have a problem.I went to the bank today and was assisted by Gloria,who stated she cant promise that this problem will be fixed as its the system that does it.I really feel angry about this as i am being inconvinienced by the bank.I have transport,rent,food and other creditos to pay.