Hi @Ros,
Welcome to the Roku Community!
We suggest unplugging your device for 5-10 minutes then plugging the Roku TV back resolves the issue. If the issue still persists, please contacts your TV's manufacturer directly to report this issue and request additional support. Each Roku TV manufacturer provides direct support and warranty services for their products running the Roku OS.
You can reach them here: support.tcl.com/us or at 1-877-300-8837.
Many thanks,
Mary
Mary F.
Roku Community Moderator