FNB REVOLVING CREDIT NIGHTMARE

I have a revolving credit with FNB which I have had since 2017. In the last couple of months under very trying times I have paid extra into the loan facility and was reducing the capital amount every 2nd or 3rd month. Since 2017 I have NEVER defaulted on the loan. Now due to unforeseen medical expenses I requested if the loan could be increased to the original amount, which is not much more than what I have currently and I was declined due to AFFORDABILITY. When I asked if someone from the decision making could contact me, i.e the Credit Manager I was advised they don't make outbound calls. FNB PLEASE EXPLAIN TO ME WHY I WAS DECLINED ON AFFORDABILITY WHEN I HAVE NEVER DEFAULTED AND PAY MORE THAN THE REQUIRED AMOUNT ??? Also I am one of those clients who are well aware of their credit rating, I know I have an above average credit rating.