_spf.amocrmmail.com has no NS records.
NS records for this zone are defined at amocrmmail.com.
NS records for this zone are defined at amocrmmail.com.
Question and response
Question
dig _spf.amocrmmail.com. NS
Answer
The response has no answer records.
Authority
amocrmmail.com. 600 SOA ns3-l2.nic.ru. dns.nic.ru. 2017100222 1440 3600 2592000 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0