If you have already registered your Sony Bravia Internet Video device on Sony Essentials website and able to stream videos from Netflix, then, it is not required to register the device again. Refer to the below link for information regarding how to link the Bravia Internet Video device to your Pandora account.
However, if you are getting a registration code field while logging in to the My Essentials account, then the device is not registered successfully. A code will not appear if the product was previously registered. To resolve this issue, contact the Customer Relations team at (239) 768-7547 to speak with a customer service representative.
If my post answers your question, please mark it as an "Accepted Solution." Thank you for your post.