Deducting debit order before set date? Why??

To whom this may concern, my husband banj account- Fnb tired to debit his account for a loan he has twice? Before the set date. The loan debit order goes off on the 25th of every month. Which he pays every month, no missed debit order! Why did they try to debit his account on the 13th of December and again the 18th? I demand that he will not be charged penalty for 2 bounced debit orders. He has not been paid yet as his salary is only going to be paid in on the 21st of December. I and my husband want to know why his account was debited before set date? He always pays his loan on time and never missed a debit order. Who is going to fix his credit score now as it will show 2 bounced debit orders. We want answers as we are not happy. FNB we have both been loyal clients for years. This will cause us to move to a different bank. We will stop the debit order and eft money when it suits us. This is not on and would like FNB personal loan department to contact my husband and explain what has happend and fix their mess.