P7-L10 need help

so i have this P7-L10
all i have it’s only fastboot modenot power on only logo and i’m not able to flash any stock firm ot reroll firm. (i try about 25 flash file)even 3button flash not wotk
i need to unlock bootloader then i’m able to flash anything
to unlock bootloaderi have to power om the phone (no way)
to get bootloader code on https://emui.huawei dot com not work anymore
so is there any way to get bootloader code only in fastboot mode?