This seems to be a 5 or more year old set so problems are not unheard of. Ask your TV tech to try the usual removal of the back cover to use the canned air to be sure all dust is removed. They should check if any heatsinks have fallen off and remedy that. Button it back up and re-test.
After that get estimates for the repair.
Need help, my Samsung smart tv model number UE46ES7000 keeps switch of then back on. I've tried resetting and changed all the settings but nothing works. New TV or easy fix. HELP

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