Nedbank Credit Card

I was approved for a credit card and then requested an increase in limit, it was declined and since then its been a mission to re instate the original credit limit on the account, Cannot believe that no one in the credit card department can re instate the original credit card. now the system is on block due to the credit applications on the system. There must be a solution to this as I feel this is very poor service and lack of skilled staff to liase with in resolving the issue.