I'm not reciving mails! help!

I'm not reciving mails! help!

People who sent us emails are receiving (This is happening with all our emails):

" Delivery Status Notification (Delay)"

Delivery to the following recipient has been delayed:

      info@mediainvest.com.ve

Message will be retried for 2 more day(s)

Technical details of temporary failure:
DNS Error: MX lookup of  mediainvest.com.ve  returned error DNS server returned general failure


PLEASE HELP!!