To update WHOIS information.
Login to your account -> My Domains -> Manage Domain -> Update the WHOIS contact information
There are 3 different types of contact information for each domain: Registrant Contact, Admin Contact and Tech Contact.
It is possible to keep the 3 types of contact information similar. But it's important to keep all the information up to date. Be sure that you can access this information such as email and phone number, because this data confirms that you own the domain name.