I can hear everything but i cant see anything .

Alright so i have this samsung series 5 tv and it’s not really that old and there is something wrong with it , i can hear everything but i can t see anything and if i put a flashlight at the tv i can see the screen. Yesterday it was black like that for a few mins then i got back but never black screen this much. I don’t want to open it or go to a repair shop because it might not be the backlight. What can i do?