If you're the Primary Contact for your account at Sage, you manage your contacts via Customer Portal.
If you're not the Primary Contact, the system will show the Primary Contact's name when you attempt to update the contacts.
Contact Sage Support to update the Primary Contact.
Adding a contact grants them access to product support and all Customer Portal benefits, except contact management.
See how to transfer your product license to update your company address.
Sign up to access the Sage Customer Portal
How do I update my credit card info for my account?