Debrand Huawei p9

Hello everybody, I am trying to debrand my new Huawei p9. I have tried the dload method explained in the development section but I can't manage to make the upgrading start: when I press both volume buttons and turn on (with the downloaded dload folder inside the micro SD) the device simply vibrates two times and then reboot. Do you know if I am doing anything wrong or if there are other methods? Any help would be appreciated. Thanks a lot

PS: I'm sorry if I am opening a new thread but xda doesn't let me reply to the original thread because I don't have the right to post in the development section of the forum.:(