China: First of all, please go to System Settings-Backup Reset-Pay attention to restoring the factory settings (restoring the data on the mobile phone will be eliminated).
China's second method (you can't enter the system after the brick, and the mobile phone forgets the power-on password to enter the system during operation)
China 1, the first mobile phone was completely turned off.
2. Then turn it off completely. When the mobile phone is turned off, press and hold the volume button+volume down button+power button for a period of time, and it will enter recovery. The recovery button on the volume button represents selection, and the power button confirms.
China 3, after entering the recovery mode, double clear, no matter whether your mobile phone system is restored or the third party is restored, as long as there is [Erase data/return to factory] (China version is: erase all data), erase the cache partition [] (China version is: erase all caches).
China 4, select [Erase data/restore factory settings] (China version: erase all data and restore factory settings), then press the power button to confirm, and then select [Yes-delete all data (Yes-erase all data).
China 5. Select [Clear cache partition (China version: Clear cache)], then press the power key to confirm, and then select [Yes-Clear cache] (Yes-Clear all caches).
China 6, then select 【 System Restart Immediately 】, and then press the power button to start the mobile phone for confirmation.