@umeshpatel first we would really need to know the exact make and model for your TV. Then you need to make sure that you have a good power outlet. Make sure that it is the TV and not the outlet that loses power. Make sure that your power cord is properly plugged into the TV.
IF none of that works, return your TV and get a different one. You said it was new. A new TV should never do that and you should not have to fix it before using it.