Weed Eater One

I've had this weed eater brand blower for about a year now, it came with a 2 year warranty. About 3 weeks ago it would not start it had new gas in it and I replaced the spark plug. Still would not start. Call and found a repair center took it there. After going back and forth with them for 3 weeks was told that weed eater was not going to stand behind the warranty. They told me it had scaring on the cylinder walls, I'm still trying to understand how that is my fault.