Huawei Y6 SCL-L01 remove branding TIM

I have Huawei Y SCL-L)! with Tim Ita. branding on it.

I wont to flash this Y with non branding firmware, but everytimeit failed.

update locale with dload on sd card is not working
update with 3 button is also not working

bootloader is unlocked frp is unlocked when i put phone in fastboot/adb mode on pc.

i tried with extracted filed with flashboot flash:
cust but allways cust failed

Somenone can help me ?