WHY THE HELL WOULD YOU DEBIT MY ACC SO MANY TIMES!

I can not even begin to tell you how upset i am with the way you have handled my account at standard bank. This is so wrong on so many levels that you would debit my account in one month a total of five times!!!. My debit order date on my RCP loan which is the only product and the last i intend on having with you guys is the 20th of each month, for this month i want to know why would you debit my account a day prior to the debit order date that was set as the 20th fell on a saturday! why not take the debit order on the next working day. standard bank debited my account twice on the 19/06 which rejected , still debited my account on the 20th( A SATURDAY BY THE WAY), i then called your call centre on the 22/06 and had my debit order changed to the 25th of every month GOING FORWARD to prevent such issues from occurring even though you guys were wrong!!! However to my surprise this morning i see you debited my account twice today!!! and it rejected. I do not understand why would you this, you have now compromised the status of my account and my credit scoring by debiting my accounts a number of times when you were not supposed to, PLEASE DO TELL ME HOW YOU WILL FIX THIS !!!!!!