How to change my linked Netflix account?

How do I change the Netflix account linked to Xfinity StreamSaver? These approaches didn't work:

* Signing out of Netflix and signing into a different account.

* Canceling StreamSaver and singing up again.

* Asking Netflix to unlink Xfinity as my payment method.

* Canceling the Netflix account Xfinity is linked to.

I spent 4+ hours on chats and on the phone with various Xfinity and Netflix representatives trying to solve this. What's clear is this is an Xfinity problem, not a Netflix problem. No matter what I do, Xfinity remembers the linkage. When I follow the steps to "Activate Netflix" for StreamSaver it says Netflix is already active, even though my original Netflix account doesn't exist anymore. Xfinity must have database that needs resetting, but nobody on chat or phone support has a clue what they're doing. Please help.