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.
Premium subscriptions purchased through 3rd party systems like Roku, Amazon, Hulu, Smart TVs, etc, are often only viewable via the service through which you subscribed. In Roku's case, most (all?) are viewed via The Roku Channel.
If you want to view on all platforms supported by that channel you typically must subscribe directly with the channel via its web page then use its dedicated app for each platform, authenticating via your channel account.
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Roku Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X | Roku Streaming Stick 3600