I keep receiving the same submission?

One of our forms "Training Week 3 Feedback" I keep receiving the same submission over and over again. Please can you tell me how to stop this? 

Good morning this is the form that had the problem.
http://www.jotformeu.com/OakwoodCanineServices/3_Week_Feedback
Thanks,
...

I've just had that, I think my problem is because the form isn't clearing and the user thinks it hasn't sent. does your form clear when you do a dummy submission?

The form wont clear if you have enabled the auto fill feature since it saves the most recent form data in the browser for specified period it then auto-fills the same form with this data.

You can turn off this facility if you don't need it for the particular form.