How can I get my Llumia 520 to restart?

[Saicharan Pardhu]

lumia 520 restart problem

Hi guys , my lumia 520 won't restart , and only shows the Nokia logo followed by the exclamation point for about 15-20 seconds when I plug it in. It then cycles back off and on to the Nokia logo again, rinse and repeat indefinitely..and my volume power and camera buttons are not working to start with kind of urgent:unhappysweat:

 

[Saicharan Pardhu]

Re: lumia 520 restart problem

solved,just the volume down buton was pressed during restart