ns03.intrabit.net has no MX records.
Question and response
Question
dig ns03.intrabit.net. MX
Answer
The response has no answer records.
Authority
intrabit.net. 86400 SOA ns01.intrabit.net. domains.intrabit.net. 2026021500 43200 7200 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0