Unauthorised Debit order

<p>My name is Ndumiso Mayisela, I bank with FNB. I took a loan from them 2 months ago and I have been managing my account well, meaning that it has never been in arrears and I R5499 for this loan . Today I received a call from an FNB agent (I can't remember her name), when I picked up she demanded to talk to me, I said yes its me, she then wanted me to confirm my ID number, I told her I was busy she must call me after 17:00 today 2016-11-18, when she called after 17:00 I was already driving home, I couldnt pick up. Imediately after her call I saw and SMS notifying me of R4302.17 leaving my account. I then later received an SMS saying "MR MAYISELA, we have deducted R4302.17 due to arrears on your FNB Loan"</p> <p>My problem is: Firstly, my FNB Loan is not in arrears (the instalment gets deducted before it even hits my account). Secondly, I would like to know if is it legal for the agent to debit money from my account without my consent?</p> <p> </p> <p>This has inconvienced my greatly because i have other commitments that I need to use this money for.</p> <p> </p>