On this page we shared Tutorial Flashing Panasonic T21 software damage due to an error that we could do alone. for example, the process of rooting failure or installing applications that bring wallware or virus. could lead to weaker performance of mobile phones, until Hardbrick. but as long as it is detected in the computer driver. you can still correct it by re-install the firmware. or if it still lets you also can perform recovery mode or reset the user data. but sometimes the damage is not quite in this way. You also need to update your Android phone.
Download and extract the SP Flash Tool and Mediatek USB VCOM drivers
Install the driver if not already installed
Download and extract your ROM package and find the scatter.txt file.
Run Flash_tool.exe then click Scatter-loading button to load the correct scatter file
Turn off your phone, remove the battery and replace it after some seconds (and don't turn on the phone).
Press F9 (or hit Download button) and connect your phone into the computer via USB data cable. The process will start and a red progress bar will appear.
After the red progress bar is complete, there will appear a purple progress bar.
Right after the purple progress bar is complete, a message will appear underneath it: “Please insert USB cable in x seconds” and then the download will start right away (you will see the yellow progress bar filling up).
When the yellow bar is complete, you'll get a popup with a green circle and Download OK message, which means that the process has been successfully terminated.
You can now safely disconnect your phone and turn it on. The process ends here.
