After the latest update my phone display has 4 green lines
iPhone 12, iOS 16
Question marked as
That does not look good. That is a sign of a failing display or logic board. If you take an internal screen shot and those lines appear in the image, then it is the logic board and if there are no lines in the screen shot image, then it is the display.
My recommendation is that you have your iPhone examined at the Apple Store or at an Authorized Service Center for further diagnosis and a resolution.
Axel F.