_spf.studioavw.nl has no CNAME records.
Question and response
Question
dig _spf.studioavw.nl. NS
Answer
The response has no answer records.
Authority
studioavw.nl. 88 SOA ns001.auroradns.eu. admin.auroradns.eu. 2018032901 86400 7200 604800 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0