That is not any sort of configuration controllable setup. Something is broken.
How old? Any warranty?
You can probably take it to a repair shop for a diagnosis. They will charge for doing that but may "subtract" the diagnosis charge from the repair costs (materials and labor).
And their work may be only guaranteed for a short period of time. And you really do not know if another failure is actually their work or something else.
Find out the cost of a diagnostic check. Then decide if you wish to risk that amount (plus potential repair costs) or just buy a new TV.