FNB poor customer service

I have been banking with FNB for many years. So very much disappointed with the service I have been getting from them. I paid up a personal loan a week ago. I am struggling to get a paid-up letter for a week now. After about 15 calls and so many attempts on the secure chatt function on the app, still no success. Gets disconnected on almost every call. No call back to resolve the matter. Paid up a loan at Capitec and within half an hour it was sent to me without even me requesting it. Still do not have the letter.