have set to flap off=hibernate but when i slide my flap it restarts rather than hibernating.

Before we start with the troubleshooting steps, I would like to know some information about this issue.

1. Were you able to change the Hibernate settings?
2. Do you get any error code or error message when you start the computer?
3. What is the make and model number of the computer?

I would suggest you to try the following methods and check if it works for you.

Method 1:
Run the Power Troubleshooter and check if it helps.
Follow the steps to run the troubleshooter:
a. Press Windows + W keys on your keyboard to get the search option.
b. Type Troubleshooting and click Troubleshooting.
c. Now type Troubleshooter in the search option.
d. Click Power Troubleshooter and follow the prompts.

Method 2:
Change the Hibernate settings once again and check if the issue persists.
Shut down, sleep, or hibernate:
http://windows.microsoft.com/en-us/windows-8/how-shut-down-turn-off-pc
Note: Refer to the section "Hibernate".

Method 3:
Create a new power plan and check if it works.
Power plans: frequently asked questions:

http://windows.microsoft.com/en-us/windows/power-plans-faq#1TC=windows-8