Your domain’s name servers can be modified in the “Name Servers” section of the Domain Management Interface
Once the correct Name Servers are listed, it normally takes 24-48 hours for the change to propagate to all computers on the Internet. However, the configuration of the Name Servers themselves is an important factor as well. You should consider speaking to the administrator of those new name servers to find out if they have also been configured correctly for your use.
If a domain is not resolving the way you expect it to, you should contact your Name Server (DNS) Administrator or your Provider for assistance.