How to factory reset OPPO A51? How to wipe all data in OPPO A51? How to bypass screen lock in OPPO A51? How to restore defaults in OPPO A51?
The following tutorial shows all method of master reset OPPO A51. Check out how to accomplish hard reset by hardware keys and Android 5.0 Lollipop settings. As a result your OPPO A51 will be as new and your Qualcomm Snapdragon 410 MSM8916 core will run faster.
BacBa - Hard Reset OPPO A39 (Neo 9s) - video
Hard Reset will erase all of your data
All described operations you are doing at your own risk.