How to fix "Screen become black of my Mi Note Mobile "

[AC Question]

I am having Mi Note for the last one year. From the last two days, my mobile screen is blurring and become black and it is idle for long time. Moreover, i can receive calls but i am not able to make a call. After some hours the screen will appear and it will work for some hours then again blurring and black. Can anyone tell what is the problem and how to fix it?