capitec unable to change debit order date

I have a student/loan with Capitec bank. My salary gets paid between the 22-25th of each month. There is no constant date. I've contacted and gone into capitec bank and advised the consultant to move my debit date to the 26th of each month. The system is not allowing them to do this I get called and sms's of late payment. This same bank sends you so many smses to make constant loans upon loans. Capitec should really sort out there system I pay for there calls to me and for letters. Yet the, clients are harrassed for payments we pay capitec monthly!! I'm the same person that must pay arrears, when you habe a **** system. So stop *********** clients.