mail.glowingblue.com has no MX records.
Question and response
Question
dig mail.glowingblue.com. MX
Answer
The response has no answer records.
Authority
glowingblue.com. 3600 SOA ans02.89grad.ch. root.ans02.89grad.ch. 2026021201 3600 600 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0