You can request a domain name change as long as your Kayako license is kept within the same organization and ownership. In other words, it is not possible to transfer or sell a Kayako license from one organization to another.
You will need to contact the Support team to add, remove, or update a domain name. As part of the authentication process, you'll need to provide either your Order ID or any of your Transaction IDs. These can be retrieved from your my.kayako.com account.
NOTE: Your subscription must be active in order to proceed with the changes.