Hi, @Rebecca24.
We appreciate you reaching us here in the Roku Community!
We understand that you're having an issue with your TCL Roku TV screen that flashes red and white.
In this case, it could be a hardware issue, and it is highly recommended that you directly raise your concern to your TV manufacturer. We only support your TV's running software operating system, which does not include hardware issues.
You may reach them at TCL Support
We hope this will be sorted out soon.
Regards,
Reynan
Reynan L.
Roku Community Moderator