FNB-This is not **** Germany.

I've asked to downgrade my CC from Private to Premier. This is still in the process. I received a SMS saying I've exceed my limit by R30k. This is the first time I hear of this. When speaking to Thato, she says that the person who submitted the paperwork, decided what the limits should be. Now who gave FNB this authority to do this. Why was I not told about this when applying to downgrade. The crazy part is that I have funds in my credit card, but I've exceeded the limit. Can someone please explain this to me. I was sent from pillar to post, speaking to 4 different people. The 4th person decided to terminate the call. What do I do?