spf.openminds.be has no CNAME records.
Question and response
Question
dig spf.openminds.be. NS
Answer
The response has no answer records.
Authority
openminds.be. 1309 SOA ns1.openminds.be. hostmaster.openminds.be. 2772532389 14400 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0