FNB home loan division

FNB has provided me with great service over the years. I am just disappointed in the home loan division, I had requested that the additional amount that I pay on the home loan must be capitalised on the loan for it to decrease.the additional amount no longer reflects however the total amount on the home loan increased instead if significantly decreasing on the outstanding debt. This makes no sense. I called the division with no assistance, I further requested if I can reduce my payment terms and the lady informed me they can’t do that however through the secure chat I was informed I can apply for th e reduction. This is really frustrating as I am trying to pay the home loan faster.