What's going on with my phone??

[Doctor_Who]

Today on the way home my 640 just stopped. I couldn't turn it on, nor could I turn it off. And I charged it before leaving work. Why would it just .... whatever it did?

 

[Chintan Gohel]

Today on the way home my 640 just stopped. I couldn't turn it on, nor could I turn it off. And I charged it before leaving work. Why would it just .... whatever it did?

Press volume down and power button for 15 seconds together until the phone vibrates and restarts. See if that helps