Hi simonetomasi84,
Welcome to Sony Community!
Sorry to hear about this inconvenience. What has changed prior to the issue? You may try to boot to Safe Mode and then replicate the issue. Try also to go to BIOS page and same thing replicate the issue. If it persist on either of the two steps then I strongly suggest to bring the laptop to a lapop repair center to have them thoroughly diagnose the unit.
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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