mcb-04.lynero.net has no MX records.
Question and response
Question
dig mcb-04.lynero.net. MX
Answer
The response has no answer records.
Authority
lynero.net. 600 SOA ns.lynero.net. hostmaster.lynero.net. 2026030503 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0