Thank you for your message.
Has there been any accidental damage, like the notebook being dropped or something heavy kept on the lid?
Run a hardware diagnostic by following this link http://bit.ly/2fJuGXB & check if the issue persists & if there is any error code listed.
For better assistance, please click on my Dell username & send a private message with the service tag, registered name, email address & an image of the screen.
Dell-SreejithR
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