Hi WimadS,
Welcome to Sony Community!
We're sad to hear about what happened to your screen. You said it was ok yesterday and nothing has changed? No physical damage or liquid damage? It's strange that the screen suddenly shows dark spots. Kindly turn off the laptop then go to BIOS. If the screen looks normal and no dark spot then reset the BIOS to default setting but if the dark spot exist repair is needed for your laptop.
We kindly recommend visiting our Sony Global Web site for information on contacting the Sony Support Center in your region at http://www.sony.net/SonyInfo/Support/.
Regards,
Jen
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