Thanks for reaching out to the Roku Community.
Have you tried unplugging the TV from the power source for 10 - 15 minutes and see if it helps? If you have not tried it yet, kindly do this to your Roku TV and see if there's any difference after.
If still no luck, follow the suggestion posted by @RokuMary-F above, kindly contact your TV manufacturer directly to report this issue and request additional support.
In case, you have a different Roku TV brand, you may refer to this list of Roku TV manufacturers' contact information, visit our Community post here: Contacting Support for Your Roku TV
Please let us know if there is anything else we can assist you with.