The latest update to the TV app (5.6.1) on Roku stick and Ultra broke the favorites filter that had been working. I've removed and reinstalled the app plus restarted Roku still does not work on 3 different Roku devices. Must have missed that on their testing, very frustrating.
Actually filters have been broken on the app since the version 5.2 upgrade in September. There have been previous posts about it. It seems this is a low priority item for Spectrum.