dns configuration on dedicated server

We have rented a dedicated hosting server and have WHM installed on it. We have created a cpanel hosting account using the whm. We have set up private name servers on the server. For one of our hosting accounts, the domain (registered at godaddy) keeps pointing to the old hosting server at Yahoo and so our old website keeps showing up to the visitors. We want to solve this issue so the new website hosted in our new dedicated server shows up.