smtp.afrinic.net has no CNAME records.
Question and response
Question
dig smtp.afrinic.net. NS
Answer
The response has no answer records.
Authority
afrinic.net. 3023 SOA ns1.afrinic.net. dns-admin.afrinic.net. 2026030415 14400 3600 36288000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0