_spf.midco.net has no CNAME records.
Question and response
Question
dig _spf.midco.net. NS
Answer
The response has no answer records.
Authority
midco.net. 900 SOA dns3.midco.net. hostmaster.midco.net. 2018117021 10800 3600 2419200 900
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0