Unauthorized change of debit order dates

After being a loyal FNB client for the last 15 years, I’ve decided to eventually post about my extremely unsatisfactory experience I have annually with this bank. Every single December, FNB changes (without my consent) the date of my debit orders. As someone who only receives their salary on the last calendar day of the month, this more often than not, leaves me with a financial short fall over the Christmas season. No matter how many calls I place, this happens every single year without fail, causing me to waste time and money trying to get these debit orders reversed, which is always at my expense. Starting to think that my Christmas present to myself this year will be a change of banks.