@Meredith183, sorry, but you'll find many, many reports of the same thing. Try unplugging the power for an extended period like overnight and see if the picture comes back. If it does, turn down the brightness. That may keep it from happening in the future.
If it doesn't come back and if you can shine a bright light on your TV and see a picture, something within the TV has failed. Replacing the failed component probably isn't something the average user can do, but you can search the Internet for instructions and what you'd need to buy.
It would be TCL's responsibility, but given that it's long out of warranty they won't help you.
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