Poor treatment by personal bankers and line manager

I have noticed an increase in my monthly bond repayment since i started paying extra money into the account this 2024. And the manager Ms Paamaalai Padayachee cant even point me to the exact clause in my home loan contract that explains this increase. So why is Nedbank Punishing me for making extra payment into my bond account??? Just like the manager, the personal bankers keep on saying they will make follow ups and its months now with no success. But money is being deducted from my account every month.