Poor service delivery

I went to the FNB branch in Pretoria North in July 2015 to change my debit order date on my personal loan from the 27th to the 1st day of the month. I also requested for my debit order instalment to be reduced. The agent (Pemla) informed me that it can not be done but she will change the debit order date for me to the 1st. Today when I checked my bank balance I saw that the instalment for the personal loan were made today and now I don't have money to pay doctor fees and fuel for my car. After I spoke to the agent from FNB on 27/11/2015 he informed me that there is nothing he can do for me and will only be able to assist with changing the date on the 30th of November, which doesn't resolve my immediate issues. I am very unhappy with this type of service and think this is very unfair for me as a loyal client not to be assisted in my issues.