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Its not the usual black vertical line it is a thin vertical line on the corner of My iphone 5 i replace the screen of my phone 3 Weeks from now and now it has vertical line i dont know what happened i was shocked because it has line now only one solid super thin line on the corner what this could how to solve it should i replace my screen again ?
Have you tried cleaning the connectors with isopropyl alcohol? It could help. Also, try moving the LCD flex cable when looking at the screen turned on, check is there is any change to the display, if lines are appearing disappearing you could have a unit with a faulty flex cable.