FNB debits Whole amount From Credit card without my authority.

I have a business credit card with FNB since 2012. In 2017 business became slow. This put us in a financial jam for over a year. My credit was put on hold and handed over to legal department. I explained to the legal department many times that I am undergoing financial difficulty and has soon as business starts to do well i will happily pay of the balance.

The account was handed over to Brooks N Luyt Attorneys and on the 31st January FNB deducted the whole amount of R20489.12 from my business account. I called FNB and tried too resolve the matter and explained to them that the funds are not mines and has been catered for already. It was commitment money and that I have to pay a supplier and Vehicle finance which I am in arrears with together with my January rent. they then advised me to call the attorneys handling the account and I did which they heard my story and said :Kindly note that we have escalated the matter to our client and will revert upon receipt of feedback. 3 days later the attorneys for FNB calls me and says that FNB will not be able to refund me due to non payment. I called FNB again and pleaded to refund atleast R18000 back and take R2489.12 towards the credit card and each month R1000 which we now will try and commit to. The agent said sorry but the account is settled and they will not be able to refund again due to non payment. My question is why does the bank have to take out the whole amount when every month they are receiving interest on the credit card. I also have a overdraft facility which they are also deducting o monthly fee. why couldnt they also deduct a monthly fee instead of taking out the full amount without my permission. we always paid on time. Every business has ups and downs. We are they client and they receive interest every month without failure.

I am very disappointed with FNB client relationship. They moto is FNB how can we help you, but instead they have now put me in a jam with my vehicle finance and other accounts. I understand that I owe them but without my knowledge they see funds available and then debit as they please. This is not fair. I had deadlines on the 7th of this month which i explained humbly. I also noticed that every time funds are available in the business account FNB will debit different amounts. where does this money go to because it does not show in my transaction history. I even called the business banker to find out and he said its my credit card and overdraft facility and will not show in transaction history. Find that hard to believe . I am devastated with FNB and hope they dont treat all they small clients like this.