We were sent a contract to sign that we did not receive.

One of our clients sent us a document to sign on 7/12/2017. We never received it. In the last day or two this was discovered and discussed and the document was resent. We did not receive the document after this second attempt. I checked our email server and I see a number of emails that generated SMTP receive exceptions from <bounces@mail.na1.echosign.com>. I want to guess that these were secondary messages to say the primary message did not go through. I cannot find any email log of the primary message. The only messages I see log of from echosign are from the bounce address. Is there a whitelist we have to apply to?

Thank you for your help

Andrew Becker