Dispaly Backlight Not working

I have Macbook Air 13" Early 2015 model. For few weeks display brightness was inconsistent and keeps flickering. I thought this might be due to Ambient sensor and I turned it off. After some days the display backlight went off and comes back if I adjust the screen.

Now the backlight never comes back except only once when I press at both top corners of screen .

The store people ask me replace the entire screen which cost around 45K INR . This is costly for me to afford at this point.

Kindly help me if there is anything which I can fix .