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.
Been wanting to watch The Plot Against the President. It is currently available on two services that R O K U supports. But when I try to watch I get a message that I can’t watch it via ROKU and I need to watch on another device.
please be honest...why am I not able to watch this documentary?
I think you should contact those services and ask them why they're not making it available via Roku. I don't believe Roku has any input into what a service offers or doesn't offer. Keep in mind that there's always been a difference in providers' minds between making something available via a computer screen and making it available via a television screen.
For more information about that channel's content 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.