MFC deducted installment after settling the car

I owned a car that was financed by the Motor Finance Corporation (MFC). The car is written-off by the insurance and settled the outstanding amount with the bank (MFC). The bank (MFC) continued to deduct the money even though I don't owe them.

Therefore, yesterday on 28/07/2020 I called MFC and the person who picked my call was rude. The fact is they deducted my money which they were supposed not to deduct and they are supposed to refund it because I have budgeted it for something else. Now the lady didn't even bother to listen to my point instead she ridiculed me. If it was me skipping payment they were going to charge me interest per day. Now because is them, they are even willing to keep my money for 5 days.