server.ubuntubackup.bg has no MX records.
Question and response
Question
dig server.ubuntubackup.bg. MX
Answer
The response has no answer records.
Authority
bg. 10800 SOA a.nic.bg. hostmaster.register.bg. 2026030104 10800 1800 2592000 10800
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0