FNB don't give a toss about you!

FNB have zero interest in customer service. I have been trying to get a refund from them for over a month now, 3 amounts have been refunded successfully but the 4th amount (over R1600) has yet to be returned and I keep getting asked for the same proof of payment that I have submitted multiple times. I have changed banks since FNB had zero interest in retaining my business, after being shifted from person to person I eventually said I'd like to close all of my accounts and simply got a "no problem" response. to this day I have not been contacted by anyone asking why or what they could do to keep me on board! All I want is my refund so that I can move on and never give a second thought to FNB and their pathetic levels of service, that after almost 30 years of being a client.