Automatic switching from "Hibernate" to "Sleep"

This could happen if there are any scheduled tasks assigned to the system that is making the system to go to sleep mode, also the Microsoft automatic updates run at 3AM every day if they are set to automatic...

try the below troubleshooting steps that may work:

1)turn off automatic updates
2)clear all the scheduled tasks assigned to the system( to check the scheduled tasks -> click on start in the search field type task scheduler)
3)Disconnect all external devices connected to your notebook (USB mouse, kb, pen drives ect)