Unauthorised Debit and Bad Attitude

I opened a new FNB account with FNB since 2009. My salary was paid into this account on 25/10/2017 after having my account frozen due to KYC being taken incorrectly. On 25/10/2017 a debit of R3,270.28 was taken off my account. After I enquired I was told it was for a credit card debt dating back to 2009! I was so surprised as I have not received contact regarding this account. There was no judgement or default on my credit report for this account. I contacted the legal department. Spoke to Lebogang who very rudely informed me that the bank was entitled to do this and they will not refund me.

FNB has left me with R980 to survive for the month and pay my rent.

My question to you know is: Is this fair practice? Where, in terms of the NCA do I qualify for this debt with affordability? This is prescribed debt.