How to remove the green verticle line from my screen

Hi nelson,

It's been my experience that green lines on the screen are almost always a result of damage to the delicate connections between the flex cable going to the motherboard and the LCD itself. Unfortunately that kind of issue is not repairable so the only solution is to replace the screen. Here's the iFixit guide showing you how to do that.

Samsung Galaxy S7 Screen Replacement - iFixit Repair Guide

You can support iFixit's repair efforts by purchasing the screen directly from them or you can find a replacement on many sites across the internet such as Amazon, eBay and AliExpress among others.

Galaxy S7 Screen: AMOLED Display + Digitizer Replacement Kit - iFixit

I'd suggest the Fix Kit version, as it comes with all the parts, adhesives and tools needed to do the job right for a minimal extra cost.