_spf.kcac-smtp.kakaoenterprise.com has no NS records.
NS records for this zone are defined at kakaoenterprise.com.
NS records for this zone are defined at kakaoenterprise.com.
Question and response
Question
dig _spf.kcac-smtp.kakaoenterprise.com. NS
Answer
The response has no answer records.
Authority
kakaoenterprise.com. 600 SOA ns-1.awsdns-00.com. dns.kakaoenterprise.com. 1 7200 900 1209600 600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0