Why do I get a black vertical line on copies when using the paper feed
How do I get rid of a black vertical line on copies whenever I use the automatic paper feeder?
Vertical black lines are usually caused by a speck of dirt or other debris on the scanning glass. In your case it will be on the glass strip under the ADF unit.
Here’s an image from the user manual to show where and how to clean.
(click on image to enlarge for better viewing)