spf.comendosystems.com has no CNAME records.
Question and response
Question
dig spf.comendosystems.com. NS
Answer
The response has no answer records.
Authority
comendosystems.com. 1335 SOA ns1.electric.net. dns.electric.net. 1518430169 10000 1800 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0