Hi @muniraja, I am sorry to hear about that. 
Do I understand you correctly in that the device gets stuck in the boot up phase, and then powers off? If I misunderstood what you mean, please feel free to correct me!
Could you first try removing both SIM- and SD cards, and then try booting the device to see if that helps?
If it still does not power on correctly, could you try forcing a shut down of your device by first removing the back, and then holding down on the OFF-button located here with a pen or similar object? Once you've done so, charge the device for at least 2 hours and then try powering it on again. It may be wise to try charging using different power sources and different chargers and cables to make sure that it's not related to that.
If it still gets stuck on the power up screen, could you try performing a software repair using Xperia Companion to see if that helps? It could be software related if it consecutively gets stuck on the boot up phase.
Let me know how it went!
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