Lumia 520

[grandfunkygamer]

My Lumia 520 went off all of a sudden thought couldn't turn it on with the power button so I thought maybe the button was malfunctioning. I then inserted the charger to see if it will automatically boot but it also failed. Any help ?

 

[Harrie-S]

This looks like a total flat battery and your battery went in a "coma" state.
So connect it to the charger and leave it on the charger. This may take a few hours before the battery wakes up out the coma state and starts loading again.