Threatened by fnb consultant

I just received a call from FNB I was busy and requested that they call me back tomorrow. I was told that they won't call me back I must phone them. Then Almost R6000 was deducted from my savings account without making arrangements. After my meeting I called back and was told by Grace Sukhele I asked why my account was debited she said coz I didn't make payments. When I said it's unfair and I will no longer do business with fnb she told me she will take all my money from my account. I requested to speak to a Manager but was told their is no supervisors or mangers available at 15:29.