createDrmSession.403-102 in Xfinity beta app in Roku

Hi,

I recently purchased a new modem Arris SBV 3202. Prior to this my xfinity app in Roku Express Streaming Stick + was working fine. A few hours after they activated my new modem, the Xfinity app gave me the "createDrmSession.403-102" error. I spent at least an hour with Xfinity tech support who was unable to help me and advised that I called Roku. All the of the other apps on my Roku work fine. Can @CCElla or @ComcastKen HELP please!!!