Debit order reversal

I am very irrated by credit check as I did an application with them and agreed that the Debit order will go off or start next month to my surprise I was debited this month and I am a single parent and the reason for me wanting a debit order for next month was because I have to pay laybye. It was done by this person and I need the debit order to be reversed as the bank can't do it. Quinton assured me that the Debit order will go off next month, I need to get my money back as I can't reverse it from the bank. Regards Busi ***