No client loyalty for loyal client

I have been a loyal FNB account holder with FNB they have always been incredible from a service and process perspective and have always been my preferred bank and are my primary bank. I have never defaulted on a single payment on my credit card or personal loans which are debit orders on my salary date and have managed my accounts very well. I have app**** for a limit increase to my exisiting cr card however it has been declined yet I can afford to pay back and have religiously agreed to my debit order date to be the same as my salary date. I feel that FNB should conduct a manual assessment for my approval as they declined me yet nedbank and other banks have approved me however I prefer to keep my relationship with FNB. I believe that I have a solid relationship with FNB but it looks like they are letting me down. My salary on my profile has increased yet I cannot update it on the apl, it is also calculating living expenses which are none existent and apparently they cannot do anything about that as the 'system' precalculates what my living expenses should be based on my salary yet I am single, have zero dependents and still living with my parents. FNB has let me down yet I have never defaulted on any repayments with them, I guess its time to change banks. I have been with FNB for over 20 years!