How to unroot and lock bootloader in HTC desire 820? I have unlocked the bootloader with windroid, then I flashed TWRP recovery,
then I flashed supersu zip file through TWRP to root my phone.
Now I want to Unroot and relock the bootloader, but when I press 'Full Unroot' option in supersu it automatically reroots after a reboot.
How can I unroot and relock the bootloader in my phone?
I don't know if it works the same way for HTC Desire 820 @Suriya, but I have also found another procedure for unrooting.


Download Universal unroot apk for HTC Desire 820. 
Connect your device to your PC using the USB cable.
Copy the Universal unroot apk to your SD card.
Once it’s been copied, disconnect your device from your PC.
Head to Menu>>Settings>>Security on your device and enable the Unknown sources option.
Open the File Manager app on your device and install the app you copied earlier to your device.
Once the app’s been installed, launch it from your App Drawer.
Hit the button marked- “Temp. un-root (keeps backup).” Your phone is now temporarily unrooted. If you’d like to make it more permanent, click the “delete su backup” button. You can then click “Restore Root” whenever you want to bring the root back.