Ensure you are utilizing the dedicated C3520_Citrus_Setting profile found in the Flash Loader 7.5.4 Core Directories. Alternative Solutions: Standard Hard Reset
Firmware Binaries : Ensure the package includes the main system binary file (such as C3520OPEN.bin or similar) and the corresponding CSC subfolder mapping the localized code. c3520 flash loader 75 4 csc v02 citrus 218l link
Insert the USB cable while holding these keys to enter the flashing mode. Wait roughly 3 to 7 minutes
Wait roughly 3 to 7 minutes. Do not touch the cable or move the device during this phase. Search for a downloadable link for "Flash Loader 7
This is the primary software that will write the new firmware to your phone. Search for a downloadable link for "Flash Loader 7.5.4 CSC v0.2 Citrus Lite" or simply "Flash_Loader_7.5.4_Citrus_Lite". The file you download will likely be a compressed archive (like a .rar or .zip file), which you will need to extract to a folder on your computer.
Once the computer detects the device, click in the Flash Loader. The progress bar will turn yellow and start moving.