spf2.authorize.net has no CNAME records.
Question and response
Question
dig spf2.authorize.net. NS
Answer
The response has no answer records.
Authority
authorize.net. 276 SOA lloyd.ns.cloudflare.com. dns.cloudflare.com. 2019103491 10000 2400 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0