dns01.dns.pt has no MX records.
Question and response
Question
dig dns01.dns.pt. MX
Answer
The response has no answer records.
Authority
dns.pt. 300 SOA dns01.dns.pt. request.dns.pt. 2026022301 21600 7200 2592000 300
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0