Screen flickering since last year

My ZenFone 2 ZE551ML had screen flickering since last year, i searched forums and dicussion, no one able to fix this problem, I went to ASUS service center in my town, they only recommend to replace the screen with new one, i cant do that, because its so expensive. I need my phone for work, if the screen still like this i cant continue my work.
Thank you, im looking forward for your response.

Hello. Would be mind adding more details? My Z2 ZE551ML is now at the hand of my friend. And I've heard him say that the screen somehow flickers lightly when he is going to lock/turn off the screen of the phone. I haven't seen it personally though.

When i turn off my screen, and turn it on again after awhile, the flickering show up. And it wont go away, theres no solution everywhere, even from ASUS Support. I went to ASUS Center in my town, they only recommend to replace the screen with new one, they didnt even look at my phone screen, even the service is not nice..
Oh yeah, i search everywhere about asus screen flickering and see its exactly like my screen, on the same place, its 3/4 black grey line from bottom, and its like you broke the screen.