spf.naver.jp has no CNAME records.
Question and response
Question
dig spf.naver.jp. NS
Answer
The response has no answer records.
Authority
naver.jp. 600 SOA ns1.naver.jp. domain.linecorp.com. 1768957992 3578 600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0