In order to hard reset a Amoi F620, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
Amoi F620 device will be brought back to the default configuration of a brand new device.
1. Begin by powering the device on.
2. Next, tap in one of these codes: *#94267357#, *#9426*357#, *#19912006#, *#77218114#, *#881188#, *#118811#, *#3646633#.
3. You're done, and the device should now restart.