If you wish to use the domain name registered through MYOB Atlas with a third party website; you need to move away your domain name to another registrar.
MYOB Atlas does not offer custom DNS service or other modifications to domain records. In simple terms, when you enter your MYOB Atlas domain name, it can only open website created with Atlas. MYOB can’t change your domain name to point to a website built by an external company.
If you would like to make any changes including A records or Name Server changes, please transfer your domain to another registrar who offers full DNS modification services. You can find a full list of available providers at http://dnc.org.nz//story/authorised-registrars
You will need the domain password/Auth Code/UDAI in order to transfer the domain to one of these providers. It is available on the "My Domain Names" section of your Atlas administration site or you can request it by filling Domain enquiry form. For more details you can refer to this article Transferring domain names to another registrar.
Please Note: You don’t need any release letter from Atlas - the Auth code is all you need for your transfer. Even though domain is transferred, Atlas site will be available under the default domain name and you will be charged monthly. You can opt it running and keep paying or fill out the cancellation form