I want my money back

I have two bank accounts one at Capitec and the other at Standard bank which my salary is paid to. I have a loan with Capitec and i have provided them with my Standard bank account since i get paid into that account. My loan agreement with Capitec is that they will deduct the debit order on 25 of each month from my Standard bank account.

Now someone deposited money into my Capitec account and to my surprise, Capitec has deducted the debit order for the loan from my Capitec account, even though the agreement was to deduct from my Standard bank on 25 of each month.

This is totally unacceptable and breach of contract. Can you please assist before i can complain to the Ombudsman