Debit order taken earlier than agreed

I financed a vehicle through MFC. I have asked for my debit order date to be the 1st of the month. But becuase I am paid on the 25th of the month that is what mfc agreed to. This month the 25th falls on a Sunday. So mfc decided to just take my debit order on the 23rd. This cause my account to be in arrears, is costing me money and ambarresment as other transactions are declined. I did not receive my salary on the 23rd and nowhere did I agree that my debit order can be taken earlier that the 25th. I am so sick and tired of companies moving your debit order date.