mic-hs4.gastuna.com has no MX records.
Question and response
Question
dig mic-hs4.gastuna.com. MX
Answer
The response has no answer records.
Authority
gastuna.com. 86400 SOA ns1.gastuna.com. hostmaster.gastuna.com. 2025092617 28800 7200 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0