All users can't receive emails

All users can't receive emails

Hello,
As of this morning, all out users are unable to receive emails (they seem to be able to send emails).
People who are trying to send us emails are getting the error message below. Do you know what the issue is?
Thanks.

Mail Delivery Subsystem <mailer-daemon@googlemail.com>
12:16 (7 hours ago)
to me
Error Icon

Address not found
Your message wasn't delivered to <user>@jpfm.ae because the domain jpfm.ae couldn't be found. Check for typos or unnecessary spaces and try again.
The response from the remote server was:

DNS Error: 74574593 DNS type 'mx' lookup of jpfm.ae responded with code NXDOMAIN Domain name not found: jpfm.ae
Final-Recipient: rfc822; <user> @jpfm.ae
Action: failed
Status: 4.0.0
Diagnostic-Code: smtp; DNS Error: 74574593 DNS type 'mx' lookup of  jpfm.ae responded with code NXDOMAIN
 Domain name not found:  jpfm.ae
Last-Attempt-Date: Sun, 19 Feb 2017 00:16:18 -0800 (PST)