Help & troubleshooting for channels on your Roku device, including adding/removing channels, logging in to, authenticating, or activating a channel, channel-specific playback issues, assistance contacting channel publishers to report issues, and adjusting channel-specific settings.
For more information about that channel's features and functionality, you'll want to contact the channel provider support directly to inquire further. Many channels on Roku are developed and maintained by the channel provider themselves.
I discovered this problem last month (on 6/22/2021). The News12 app on my Roku was unresponsive, so I tried updating the app. Roku indicated it was already up to date, so I then deleted the app with plans to download it anew. That plan was unsuccessful, because the News12 app is no longer available to download either from the Roku website or from the News12 website!