There are no user serviceable parts so get estimates. I got a new 50 inch via a CNET Cheapskate lead from 350USD to my door so repair OOW (out of warranty) is always a trial of CTR (cost to repair) vs. new.
While I can guess it's panel, cables or boards the tech will have to look at it and give it a try. Also against repair are trip charges. If the unit is small enough you can save the trip charge.
We have a Samsung tv probably 5 years old and this morning vertical white lines appeared and they are about 1 inch apart through out the entire screen. I have tried the picture reset and changing the inputs on the back of the tv along with unplugging it from the back. No change w anything.. Any suggestions??

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