Netflix, voucher card?

I just bought a Netflix gift card and have now started my free month. Now I wonder if I can't theoretically cancel before the expiry date of the month and then continue to have money on my gift card? Could not I create a new account every month and watch Netflix through the free months?
How is that?

Do you think you're the first one with this "smart" idea and the people at netflix are all totally stupid?

Hää wait is that possible?

No of course not. Always remember: If YOU come up with this idea, then there are already many other people in front of you. So stupid is no company that would be possible…