For Professional subscription plans, account architects can update your organizational name and/or address details via your Billing page. 

For Enterprise plans, please contact our friendly accounts team to upgrade any invoice-related information.

Your billing page can be accessed by clicking on "Account settings" in the profile image dropdown menu, top right of the main navigation bar and then "Billing". 

To change your company/organizational name, in the "Billing details" box against "Organization", click the "Update" link to update this information.
 
To update your billing address, in the "Billing details" box against "Billing address", click the "Update" link to update this information. 
 
Please note: that updating your billing country will affect your local tax setting (as applied to your subscription).