Hi @macchiata =) Nice to see you here... The truth is as you say at the end, it was very frustrating not being able to do anything because of the access problem that the BIOS had.
Disassembling and assembling the hard disk was exhausting, mentally I was about to give up, but thanks to persist I managed to solve it in the end.
Thanks for your comment =) Greetings and blessings!