Q: My IPhone 5c started showing up flashing gray lines after I updated it ***** does anyone know what to do?

Hi RodNando,

If you are getting an issue with the display on your iPhone such as you describe, I would suggest that you troubleshoot using the steps in this article - 

iPhone: Hardware troubleshooting

Specifically -

Display image issues

 

This can include bright or dark pixels, lines in video, or sections of video missing.

1. Try turning iPhone off and then on again.
2. Verify the issue is not content related, by viewing different content.
3. If the image is too dark, adjust the brightness. In General Settings choose Brightness and Wallpaperand slide the slider.

And -

Issue not resolved

 

My issue is still not resolved. What do I do next?

Contact Apple Support.

Thanks for using Apple Support Communities.

Best,

Brett L