@ hawier Welcome to the HP Community 🙂
You would have to contact HP for a hardware service as the motherboard may require a Bios Flash.
Any other way of unlocking the BIOS is not authorized by HP.
HP Technical Support can be reached by clicking on the following link: http://h22207.www2.hp.com/us-en/?openCLC=true
(1) Once the support page opens please select the country in which you're located. Next, enter your HP model number on the right.
(2) Next, choose the 'Contact Support' tab at the top and scroll down to the bottom of the 'HP Support- Contact' page to fill out the form provided with your contact information.
(3) Once completed click the 'Show Options' icon on the bottom right.
(4) Lastly, scroll down to the bottom of the page and select 'Get the phone number.' A case number and phone number will now populate for you.
Keep us posted,
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