Once you have found a valid and downloaded the .pac or .zip file, you must flash it using Spreadtrum Research Download Tool (aka UpgradeDownload.exe). You cannot use SP Flash Tool (that is for Mediatek).
: Check the Joying Firmware Page for updates related to their 2GB/4GB RAM models. sp7731e+1h10+native+firmware+link
: Perform rigorous testing to ensure the firmware and linkage feature meet all requirements and are free of bugs. Once you have found a valid and downloaded the