spf1.exponential-e.net has no CNAME records.
Question and response
Question
dig spf1.exponential-e.net. NS
Answer
The response has no answer records.
Authority
exponential-e.net. 3405 SOA auth0.exponential-e.net. hostmaster.exponential-e.net. 2026021901 28800 3600 864000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0