Download the official Huawei Ascend G620S-L01 firmware package to your computer.
You will need a reliable Micro SD card with at least 4GB of free space for the "dload" method. huawei-ascend-g620s-l01-stock-firmware-rom-flash-file
Flashing will erase all internal storage. Back up your contacts, photos, and messages to a cloud service or PC. huawei-ascend-g620s-l01-stock-firmware-rom-flash-file