If the monitor is under warranty, call and they'll replace it.  If it's out of warranty, you can either live with the issue or replace the monitor -- even if you can find a replacement panel (they're generally not available), repair will cost more than a new 27" monitor will.

Update, This morning the Black line blinking and gone for 4-5minute, 
and return again. 
What would cause this ??

It's a faulty connection inside the LCD assembly -- the monitor needs to be replaced, or it will once enough lines have formed to make the display appearance unacceptable to you.

🥹🙇 Thanks Ejn63 , I'm try not to think about it.