@antonistsi30573 you can't. Of course, you can always try a different main board (one that is not locked) but you can't unlock yours. It is the person that you bought it from that is not paying the rightful owners. That means it is absolutely not your fault, but you are the one that is now stuck with a non-working TV. Post a couple of good pictures of your boards so that we can see what you see and maybe find a compatible board for your TV.
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