nightmare when paying off your bond

My bond is paid off , lawyers gave Nedbank notice but i am being changed R9 174,29 called early settlement interest and also on the same day the bond was paid off they are charging me another R2 459,26 INTEREST . at the moment they are also moving me from one person to another when they are supposed to closed the bond account so that they can continue to charge me interests. Why **** us NEDBANK , i WANT ALL my money , my bond still have credit also payable to me . pay back my monies, why charge interest if bond is paid off , why delay to close the bond account so that it earns you more money