Why the auto-responders on the form not being sent?

I have been hearing from some applicants that they have not received a confirmation email after successfully completing a form. I set it up for these emails to be sent so why are they not sending any more when I did nothing to change the setup? 

I have checked your JotForm http://www.jotform.us/form/70184278927163 and see that there is no auto-responder set on the form to send the emails. You may add a new auto-responder to the form to send the confirmation email to the users. 

Here is the guide to setup an auto-responder.

https://www.jotform.com/help/26-Creating-a-Form-Autoresponder 

Hope this information helps!