When are you going to effect my debit order date

On the 23 of April I visited one of your branches , I changed my debit order date because my pay day has changed .I even received an SMS confirming the change of the date.Yes I didn't expect it to be effective that very month, I thought it was going to be effective the following month but to my surprise even 3 months down the line it wasn't effected and I am being debited on the 15th instead of the 25th and I am incurring charges from my bank coz my account will be having insufficient funds . Please guys when are you going to effect it coz it's now affecting me financially.<br> <br>