asus
https://androidtechpro.com/2020/01/16/how-to-unlock-bootloader-100-asus-zenfone-2-model-ze551ml-ze55ml/
https://androidtechpro.com/2016/11/19/how-to-asus-zenfone-2-ze551ml/
https://androidtechpro.com/2016/11/07/how-to-unlock-bootloader-asus-zenfone-2-ze551ml-100/
https://androidtechpro.com/2016/11/07/asus-zenfone-2-fix-bootloop-or-stuuck-logo-flash-official-stock-rom/