Humiliate their clients

I had a bank account as Private Banker with Standard Bank, and closed my accounts two years ago as a result of bad service. I went to FNB with my banking business. On Saturday 26th June, I went to MTN for a cell c phone contract. My application was to my shock decline. I never missed payment ever on any account, and couldn't believe it. I phoned ITC Transunion and got a report e mailed to me. Standard Bank reported me on different for Card Fees. I didn't even use my Credit Card. I was angry. Humiliated in front of other people by staff of MTN. I am a Credit Manager and a lot of people knows me. What will people think of me? I decide about their Credit Applications and look what happen to me, undeserved, unexpected. I went to see them on Monday, and they will investigate the matter, apologise and will reverse the amount. I couldn't believe that they think SO LITTLE about their clients to report them for a lousy R470 which I don't even owe them, at ITC Transunion. Are they uncapable or just spitefull because I closed my accounts there? I spoke to some of my clients about this, and realised that I was not the only person this happened to through Standard Bank.