Numerous customers have posted about this issue. It appears that an agent has to make adjustments on your account somehow and will do so via PM's with you for personal account info. @ComcastAlly helped another customer via thread https://forums.xfinity.com/t5/XFINITY-Stream-Website/Connect-to-in-home-WiFi-to-watch/m-p/3227733
In the meantime, please do not send her an unsolicited private message. It is against the forum guidelines to do so. I will escalate your issue to the Comcast Corporate employees that are available to these forums for you. Expect a reply here in your thread.
Hey there, UshioToTora! Thank you for reaching out here on the forums. I'd be happy to help out! Please send me a PM with your first and last name to get started.
To send me a Private Message, please click my name “ComcastAlly” and click “Send a message.”