spf.agnat.pl has no CNAME records.
Question and response
Question
dig spf.agnat.pl. NS
Answer
The response has no answer records.
Authority
agnat.pl. 8730 SOA ns1.agnat.pl. bok.domena.pl. 2006054487 7200 1800 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0