Increase denied for some reason

I recently requested a limit increase on my FNB credit card which was denied. The reason was something about my homeloan. Although FNB offered me the increase to start with after I bought my home. So, it doesn't make sense.

I only needed a R5000 increase. I was just approved a credit card from ABSA for 3times the amount. I would like to keep the credit card with FNB, but if I don't get any feedback, then I will close the account and move my credit card to ABSA. Please let me know if you are willing to assist before I go ahead with the ABSA card.