In order to manage your subscription, you need to access your Codeage account. If you have never registered for an account when you checked out, you will first need to create an account to manage your subscription.
Please check the email you have received from Codeage and use the EXACT same email address in order to create an account or login. If you don't use the same email address, you won't be able to find your order and manage your subscription.
In order to create an account, click here. Once you are logged in, you will be able to manage your subscription from that page or simply click here (you need to be logged in with an existing account for this link to work).