FNB making more money dishonestly.

In October I contacted FNB to decrease my credit card limit because their online banking does not allow for someone to decrease it, only to increase it. Further to this I'm not able to use the mobile app because apparently one can do so on the mobile app but the mobile app can not be used with a credit card to register the app so I can't use the app at all. I have been emailing the FNB Card support email almost every week, but only one response saying they received my enquiry, nothing else. It is now more than 1month later and nobody is responding to my emails - REF:***. Why is so difficult to decrease a credit limit, they make it so easy to lend more money but paying it back is not so easy, oh yes they make more money from lending more but make less from lending less, makes totally sense... SHARKS!

I've spoken to multiple people on the online chat, each person has a different story. How does a person decrease credit limits online, I can increase it no problem...