Your customer account shows all the details related to your subscription: blend, flavour, next upcoming order etc. It's also where you can make changes to all these things, as well as updating payment information and lots more.
If you're having problems getting into your account, check you're on the right store. We have a U.K. store and U.S. store and your account will be with one or the other, not both. Please also make sure you're using the email address you registered with. If you're still having problems, let us know as soon as possible.