Few people didn´t recieve the confirmation email from my form.

This is the form https://form.jotformz.com/jornadasmetropolitanas2016/trabajos-completos

I tried myself and didn´t work too  :( 

Can anyone help me with this?

Thabks in advance

I checked your account email history and I can confirm that there were several autoresponders that failed to send. You can also check this by following this guide: How to View All Your Form Email History.

However, I can't seem to replicate the issue on a cloned version of your form. During my tests, the autoresponder emails were sent successfully.

Can you please try using noreply@formresponse.com as the sender email of your autoresponder?

If the issue still persists, please let us know.
Regards.