Nedbank Home loan is a ****

In 2020 I took a home loan of R566 000 and have thus far paid R255000 in additional payment. Nedbank reduces our instalments every time we pay extra money, our loan term looks exactly the same even with additional payment. The problem is when we ask Nedbank to make the extra payment be part of the principal amount the loan term still is the same, when we ask Nedbank to increase instalments amount as to reduce the loan term still the loan term stays the same. Lastly we asked for the fees quotation fees on penalty if we decide to move to another bank, they have refused to give us that information. Please help.