spf1.eventsforce.com has no CNAME records.
Question and response
Question
dig spf1.eventsforce.com. NS
Answer
The response has no answer records.
Authority
eventsforce.com. 375 SOA pdns01.domaincontrol.com. dns.jomax.net. 2025081200 28800 7200 604800 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0