First, try to restart the phone forcibly to see if it can be used again. In addition, check whether the power key and volume key are stuck in the protective case.
Method for forcibly restarting the mobile phone:
① ① models of funtouch OS 3.2 and subsequent systems: press and hold the "power button" and "volume down button" at the same time 10 second or more;
② Press and hold the top round key 10 second or more to forcibly restart the mobile phone (NEX 3/NEX 3S is applicable);
③ System model before ③Funtouch OS 3.2: Press and hold the "power button" for more than 12 seconds.
If the mobile phone is not restored through forced restart, please take the mobile phone and purchase voucher to vivo customer service center for testing and processing.
If the black screen still appears after forcibly restarting the mobile phone, the following methods can be used to eliminate the fault:
1. The new version of the system improves the compatibility and stability and optimizes the performance. Please go to Settings-System Upgrade (some models are Settings-My Device -iQOOUI Version) to check the system version information. If it is not the latest version, it is recommended to upgrade the experience.
2. Enter Settings-System Management/More Settings-Backup and Reset/Restore Factory Settings-Restore All Settings-Restore.
Note: Restoring all settings will not delete any data or media files, but only restore all settings of the mobile phone, and some third-party application accounts need to log in again. Please make sure that it will not affect the use of the software before operation. For the safety of mobile phone data, it is recommended to back up mobile phone data in advance before operation. (You can go to Cloud Service-Device Cloud Backup-Backup Data Type-System Data-Back-Back up some backup system settings and desktop layout immediately; Cloud service-data synchronization-enable WLAN, Bluetooth, etc. Synchronize data to cloud services)
3. If the above methods can't be solved, please back up the mobile phone data in advance, and take the mobile phone and purchase certificate to vivo customer service center for testing.
Tips: It is recommended to call the staff of the service center in advance before going to ensure that the staff will go to work during normal working hours, avoid running empty, and pay attention to safety on the way back and forth.