Leave it plugged in a few hours to see if it will take some charge.
On your PC, install the Windows Device Recovery Tool found here:
https://forums.windowscentral.com/e...singleTopic%26topic%3DFA142987&token=6laYecbx
Remove the back from the 520 and pull the battery out. Plug the phone into the USB port on your computer. Open WDRT. Hold the Volume Down button and insert the battery. When the phone vibrates, let go of Volume Down. Let WDRT flash your phone.
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