Revert to an older Prezi

Hi
My Prezi link is http://prezi.com/8a0a2-xfqy4v/soccer/

I accidentally saved and exited and lost all my work - about 2 hours ago. Please can someone revert to an earlier saved version. Just 1 day earlier would be fine.
PLEASE PLEASE HELP - it's for school!
my username is c.f.parrott@gmail.com
Thanks
Graham.