Shipping and Billing address does not reset

How do i make the shipping address reset after each customer? Because every time i test the cart from different computers it retains the previous shipping address. Thanks!

The shipping address is attached to a user.
You must be trying to order while being logged in so of course it keeps your previous addresses. If you log out and try again, it will ask you your address again as it won't know who you are.

Thanks, I forgot that i was actually logging on as a user to view my website, while it is still under construction.