Your channel choices are attached to your Roku account. Add/delete on one Roku, you add/delete on all Rokus linked to that same Roku account.
That error may be caused by a corrupted memory cache on the unit giving you the error, so before deleting any channels I'd try to clear the cache first. The easiest way to clear the cache is by restarting the Roku that is giving you the error.
Depending on your Roku model and Roku version number you'll find the System restart option under Settings > System > Power or if not there, under Settings > System
If a restart doesn't do it, or if you don't have sufficient control with the remote to navigate the Roku menus, you can also restart by pulling the power plug to the Roku for a few seconds then plugging it back in and wait for it to restart.
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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