FNB your service stinks

I switched my bond and moved out of FNB. The outstanding amount was visible on my app. The settlement amount communicated to me was R 6 860 more than the on the app. The amount forwarded by the cancellation attorney was R16 938 more than the amount I was aware off. An amount of R26 228.79 more than the required amount was paid to FNB. FNB then refunded me R17275 ,87. What was the R8952.92 extra payment for? They then debit my account for R6769.23 after the bond was settled. They now owe me R15 722.15 and I have received no communication from them. This is how FNB operates. FNB has ************ business ethics, no transparency at all.