Bad service from consultant

Beginning of last week I went to the FNB Croydon branch to close my business account, the consultant assisting me told me I'll be charged a full monthly fee if I close the account, I was not happy with that because I was charged another monthly fee the previous week (I think on the 3 Sep 2018). I queried this, and then the consultant called someone who I think was the business manager to come assist, I explained to him, and he agreed that the charge didn't make sense, the two then called business banking to explain my query, and the person on the other side told them to send an email detailing this situation. On the 17 Sep 2018 I went back to the branch since I hadn't received any feedback, a lady consultant assisted me this time around, I explained my query to her, I don't think she heard most of the things I said because she was busy pressing her phone at some point, she didn't follow up on my query but went ahead to close the account. When she was done, she gave me a paper and asked me sign, I then asked her about my query, and how much was the monthly fee charged for this month, I then realised that I was charged the full monthly fee, and then I refused to sign that paper. She literally forced me to sign this paper, and we ended up having a heated argument in front of clients and the bank manager. I then told her the service she was giving me was not a good one, and she told me whether she's giving me a good service or not it doesn't make a difference in her life, all this happened in front of the manager. She then ordered me to go to another consultant if I needed assistance, that's when the manager asked me to come with her so she can resolve my issue. The manager tried to apologise for the consultant's behaviour, but I told her the apology must come from that consultant, not the manager. I still don't know why I was charged the full monthly fee because I didn't use the account for a full month, and the service received from the consultant was unbearable considering that all this happened in front of clients and the manager.