KingsleyNarh Said:
"Fixing black line on screen: My iPhone XR has now displayed a thin horizontal line down the screen now the line has become deep. How can I fix that . I have tried restart and updating but still. I have even lost all my data just to get it fix but to no avail."
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How would you define "deep"?
Determining if this is a Hardware Error:
Task a screenshot and then view it in the Photos app. If it is not seen, then it is a hardware issue. If it is seen, then it is an issue with the iOS (in which case, you'd probably have to reset this to factory settings). Go here: Take a Screenshot on your iPhone - Apple Support