Macbook Pro (2016) Screen becomes black when starting but returns after using for a while?

Hi,

I have had this problem for a very long while:

whenever I leave my MacBook's screen off (i.e. turned it off, left it to sleep, inactivity for 20 minutes with the screen off), the next time I turn it on, the screen becomes completely dark but the laptop is on (can see such when connected to an external monitor).

If I leave the screen on for like 10 minutes, the screen will start getting back to normal - from top to bottom horizontally. (sometimes I had to use my hands to squeeze the screen to help it recover faster)

There is definitely something wrong with the screen I am sure - but just very confusing why it could return to fully working after a while of staying on?

anyone knows why?