FNB POOR SERVICE AND REFUSE TO REFUND ME

I am so disappointed with FNB. On the 8th July 2020 I notified FNB about interest rate over charged @ 17.75% instead of 10.25% on my credit card (REF Rg***) i was told that FNB had an issue with the system and the matter will be resolved within 48hrs. On the 14th July 2020 I made a follow up as the matter still not resolved i was told back office is currently handling the matter and a follow up email was sent(ref: SC-***-5U9G4)

i have been making follow ups since them with team of bankers even today i contacted FNB and still not assisted the customer service is poor on the app every time when i query the agents get disconnected

I am disappointed with FNB, since the error i have been accumulating interest on my credit card because the matter is not resolved and no one is willing to assist i have call several times but i have not yet refunded