Nokia
Mobile gets Switched Off

I purcahsed a new nokia3110 CLASSIC On 13 april 08.After 1 week of purchase it gets automatically switch off and also it is getting switch on after sometime and this becomes a regular thing in the cell till i format my memory card. Is there any way to resolve this problem in the same cell or nokia will replace this cell. Please provide me the resolution as soon as possible as i'm totally frustrated with this problem.

Thanks

Ankit Jain.