mailers.dovetailnow.com has no NS records.
NS records for this zone are defined at dovetailnow.com.
NS records for this zone are defined at dovetailnow.com.
Question and response
Question
dig mailers.dovetailnow.com. NS
Answer
The response has no answer records.
Authority
dovetailnow.com. 900 SOA ns-1765.awsdns-28.co.uk. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0