These things are just special purpose computers. Like their big brothers sometimes clearing things out by restarting them is all it needs.
Depending on your Roku model and Roku version number you'll find the System restart option under either Settings > System or Settings > System > Power
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 device for a minute or so then plugging it back in.
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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