iPhone X has a green line on the left of screen. How to fix it?

Solution 1:

This issue usually comes together with issues with touch response for which there is a replacement program by Apple in which the display would be replaced free of charge outside of the regular warranty period. (https://support.apple.com/iphone-x-display-module-replacement-program)

Visit your local Apple Store or Service Provider and check to see if it can be fixed under this program.