_spf.savecom.net.tw has no CNAME records.
Question and response
Question
dig _spf.savecom.net.tw. NS
Answer
The response has no answer records.
Authority
savecom.net.tw. 60 SOA dns.savecom.net.tw. noc.savecom.net.tw. 2026011501 900 900 1800 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0