mail11516.mkt12115.com has no NS records.
NS records for this zone are defined at mkt12115.com.
NS records for this zone are defined at mkt12115.com.
Question and response
Question
dig mail11516.mkt12115.com. NS
Answer
The response has no answer records.
Authority
mkt12115.com. 900 SOA ns1.acoustic-adm.com. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0