ismtp.axcient.com has no NS records.
NS records for this zone are defined at axcient.com.
NS records for this zone are defined at axcient.com.
Question and response
Question
dig ismtp.axcient.com. NS
Answer
The response has no answer records.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0