When this channel is one for which you have a premium subscription through Roku, there will be a "Manage subscription" option instead of a "Remove channel" option. You can click this and follow the prompts to prevent further payments, but under Roku's current coding you will not be able to remove the channel through the Roku interface until the pre-paid subscription expires.
While the subscription is in force you can use the official Roku remote app on an Android/iOS phone/tablet to remove the channel from your account.
At the bottom of the app's Home screen, click "Devices" and connect to one of them if not connected already. On the Devices page, click on "Apps on Roku" and find the channel you want to remove. Click AND HOLD on the channel to be presented with options to Launch the channel on your Roku, or to Remove the channel. (A quick click will instead bring up the remote control functions.)
Now Restart the Roku to remove all traces of this channel from the Roku's memory cache.
This will remove the channel from your Roku account and allow you to reinstall it in the hope of fixing your current problem, but it will NOT cancel the paid subscription to that channel if there is one.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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