Highly dissapointed with Nedbank Customer Service

Last month on the 22nd my Flisp deposit was paid into my Nedbank home loan account, i called Nedbank and they confirmed the money was paid in,I then asked them to please recalculate that amount into my bond so that my monthly installment can decrease, they said I need to contact my banker Ismail Shiraz, i did and he said he would escallate my request to the Homeloans department, i waited till month end of February and there was still no answer, on the 8th of March i received an sms saying they've calculated my installment from R9800 to R9400.Mind you this money has ben sitting in the account from 22 of February till 8 March. I then asked my Ismail to please explain to me how did they get to this amount, i want a break down because this doesn't make sense DOH deposited R41 000 and out of this my installment is R9400 like how? it doesn't make sense at all, we apply for this FLISP to give us a breather on our HL but this didn't even make a dent like R400 is the difference. He said he will escalate my query until today when i call i get reffered to my banker as im a private client, what is the point. I'm a 1st time home owner and im very dissatisfied with Nedbank service. I haven't even received the confirmation letter that this money was paid in. I was thinking of moving my salary to Nedbank i'm not doing that anymore