mailde.docusign.net has no NS records.
NS records for this zone are defined at docusign.net.
NS records for this zone are defined at docusign.net.
Question and response
Question
dig mailde.docusign.net. NS
Answer
The response has no answer records.
Authority
docusign.net. 300 SOA a1-246.akam.net. hostmaster.akamai.com. 2014053594 3600 1800 604800 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0