That's so early for problems so you would call in to ask for the one time warranty extension and then to get an estimate.
Bob
model samsung ps51f5500
approx 18months old
hi my sisters plasma tv as started to show permanent vertical lines running from the top to bottom there is one or two just about 4 inches from left edge of screen an a large bunch on lines close together about a third way from left into screen covering about 4 to 5 inches of the screen. is this economically repairable or best sold off for spare parts.

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