You don't take money off on time

I app**** for a loan which has been approved. The agreement were that the money goes off on the 1st of every month. At the end of July they took money off before the 1st and i did not get paid yet as i get paid on the last Friday of the month. I don't want a bad record so i ended up calling in having an arogant lady on the other side upsetting me more. Finally after a dispute we arranged for the money to be taken off on last day cause they cannot do it for the 1st of every month. Then i get a message that they are going to take it off on the 27/07 and 01/09. What? So i call again having another argument and end up at manager. I had to call 4 times to get it corrected. The last day of Aug passed and no monies deducted. I now call again. Oh sorry i am told that date expired. Wth??? I have to call Nedbank to take money off. Being upset is an understatement. What can a person do or how much more clearer does a person have to be and why do i have to call for money to be taken off. Seriously!!! What is it going to take? I want to activate my normal nedbank acc but these issues i do not know.