_spf.shockmedia.nl has no MX records.
Question and response
Question
dig _spf.shockmedia.email. MX
Answer
The response has no answer records.
Authority
shockmedia.email. 3600 SOA ns1.shockmedia.nl. hostmaster.shockmedia.nl. 2025062403 10800 1800 345600 43200
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0