Submissions suddenly not being received by the addresses to which they are directed

The form submissions sent 9/20/2015 and 9/21/2015 have not been received via email to the addresses where they are set to be forwarded.  They do appear in the list of submissions within our account.  I also tried going into the submissions list and editing the submission and clicking "submit" on the bottom of the form and I did not receive that edited message either.  We had been receiving the submissions just fine for ages.  Any thoughts on where the hangup might be?

Hello,

Two of your email recipients ended in the bounce list due to the following reason.

matching@gpa-mn.org

secretary@gpa-mn.org

Reason(s) : smtp; 554 4.4.7 Message expired: unable to deliver in 840 minutes.<451 4.7.1 Service unavailable - try again later>

It seems your email service provider is unavailable by the time it receives an email from Jotform. I have now removed your email in the bounce list. It should be fine by now. Kindly check it again.

Here's how to remove your email in the bounce list for future reference http://www.jotform.com/help/262-How-to-remove-your-email-address-from-bounce-list.

Thanks!