How to factory reset IRBIS SP554? How to wipe all data in IRBIS SP554? How to bypass screen lock in IRBIS SP554? How to restore defaults in IRBIS SP554?
The following tutorial shows all method of master reset IRBIS SP554. Check out how to accomplish hard reset by hardware keys and Android 8.1 Oreo settings. As a result your IRBIS SP554 will be as new and your MediaTek MT6580 core will run faster.
Hard Reset Irbis SP455 - video
Hard Reset will erase all of your data
All described operations you are doing at your own risk.