Root and unlock bootloader

Registration date
Wednesday March 25, 2015
Last seen
December 6, 2021
Have this BLU C5L(2017-2019)-Oreo 8.1.0GO edition. I've tried multiple programs/procedures to unlock bootloader/root. I'm here because all have failed and I've exhausted( I think) the 'net" resources. There's something about this phone I'm not aware of, or so I believe. It is a bottom line phone, I know, and all I want is to getting operating as it originally did(or should have). It's a back-up, but a primary phone for now, until I can purchase a new phone. Also, finding the "original" Oreo 8.1.0GO edition(ROM) for this phone has been an exercise in futility. Well, I just haven't found it although I've spent countless hours and effort searching for it. I was warned it HAS to be ROM for this particular phone because custom or upgrades ROM's do not operate well and can possibly brick phone. Any suggestions or advice? TNX