FNB: Once, twice, three times unlucky

To start with, this is my third complaint about the very same thing on this platform. All I ever get is reference numbers and being told that my complaint is high priority and as such I will be contacted within 24-48 hrs!

I took out a credit agreement with FNB in 2018. Together with the agreement I took insurance for the instance where I should not be able to earn and thus pay off my monthly installments. When I wanted to use this insurance in November 2019 due to maternity I was told that I cannot use such insurance because I am self-employed. In the meantime, I have been paying the insurance whilst being self-employed, took the loan whilst being self-employed and really nothing has changed. On one occassion i spoke to a lady called Laurelene Vermeulen and she told me to get a letter from my obstetrician which I did. I emailed it to her and guess what, shes disappeared, no responses nothing. I have lodgeed a complaint on their website, on the app, spoke to one branch's manager about this but the matter still remains unresolved. At some point (Nov 2019) I spent a whole afternoon in the Plumstead branch on the phone for 4 hrs trying to resolve this but still nothing. All this time, I am gettting letters of demand and letters from legal department threatening to sue me. What sin have I committed? I simply trusted FNB.