I am having the same problem. What I did was i tried installing a custom recovery on a rooted huawei Che1-L04. Since the phone was rooted using Kingroot so the bootloader is locked. After flashing when I rebooted my phone, it entered into fastboot&Rescue mode showing that the phone is locked. I did the adb trick for fastboot but to unlock the bootloader I need the oem key and for that i need to enter the product id on huawei website to request the unlock key but for the product ID u need to dial a no. which I cant cuz my phone is stuck in fastboot. All i want to know is any other way of getting the product id of my phone except than dialing any no. which i cannot do due to my phn being stuck in fastboot mode. I desperately need help asap. Contact me on [phone number removed by moderator] if anyone has a solution.