tracking.epriority.com has no NS records.
NS records for this zone are defined at epriority.com.
NS records for this zone are defined at epriority.com.
Question and response
Question
dig tracking.epriority.com. NS
Answer
The response has no answer records.
Authority
epriority.com. 1800 SOA inetdns1.ssnc.cloud. dns.cloudflare.com. 2397018708 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0