smtp.webhs.pt has no CNAME records.
Question and response
Question
dig smtp.webhs.pt. NS
Answer
The response has no answer records.
Authority
webhs.pt. 10800 SOA ns1.webhs.org. reports.webhs.support. 2026012401 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0