Some of my form submissions are not being received via email

We are having customers submit forms on our site, some of them come through and some of them do not. Is there any reason why form submissions would not be emailed?

And in the future is there a way we can see when a form submission is not sent? Are there any logs we can access?

We are sending the form emails based on our logs, but it seems like you are using multiple sending methods for your form. You have SendMail, usually happens when the Attach PDF is checked in the notifier settings. You also have Mandrill, but I'm not seeing this setting anymore on your account.

Here's how to access the logs from your account: http://www.jotform.com/help/293-How-to-view-all-your-form-Email-History. 

Since we are sending the emails, it's either the emails are flagged down as spam and they are now in your spam folder or your hosting barred it from reaching your inbox. 

It is recommended to add us to your server whitelisting settings to make sure that all emails from the form are treated as safe.

http://www.jotform.com/help/145-Whitelisting-JotMails-IP-Addresses