Debit orders done outside arrangement date

Old Mutual got into the habit to deduct funds from my account before the debit order date. Athe debit order date is scheduled for my pay date, but often deductions are done the day before. I usually have emergency funds in my account and can mostly cater for the deduction. But why do I need to cater for something that's not arranged? What if there is no funds in my account? This will impact my credit rating and it's not due to my behaviour. This is unacceptable and need to stop. Nowhere on the contract did I consent for this to happen Today I've received this message again: Old Mutual: Dear MRS HOKER your premium will be deducted this long weekend anytime from Friday till Tuesday. Please leave enough money in your account for your policy(ies) to stay active. No reply SMS. FSP&Ins. T&Cs