Share your experience!
Hi @keerthimurthyks and welcome to our community!
I'm sorry to hear about your phone 
Does it show the same menu that appears if you press the ON/OFF button on your phone? What happens if you press and hold the ON/OFF button for a few seconds?
Did this occur directly after you performed the factory reset or did you restore any data or install any apps before it happened again? If you restored any data or apps, if there any change if you reboot your phone into safe mode?
Please keep me updated!
I understand. How often would you say this occurs? Is it a few times per day or a few times a week?
If there isn't any change with your device rebooted to safe mode I would advice that you to perform a software repair using Xperia Companion. Please check if there is any change before restoring any backups or data after the software repair has been completed.
Let me know how it goes!