Std Bank CPP unreasonable.

I am immensely disappointed with std bank insurance (CPP) i requested them to change the debit order for bank charges to the 28th of month end because I have changed employment and the pay day moved from the 25th which is the current debit order date to the 28th of the month which is my pay date. My account went into arrears and std bank sent me an sms to rectify my current account. When I escalated it to my personal banker she said there is nothing she can do and gave me the contact number of CPP. I called them and they advised that it is a fixed date and there is nothing they can do and I have to ensure there is money in the account on the 25th for the succesful debit. This is so contradictory because one of the options u can choose when u call is if u can't afford the charges yet they are rigid in their process from moving my payment from the 25th to the 28th.i am a regular paying customer who has not defaulted on any payments, for std bank not to accommodate the date change makes me highly annoyed. No my credit status has been impacted by this.