mail.beltcollins.com has no MX records.
Question and response
Question
dig mail.beltcollins.com. MX
Answer
The response has no answer records.
Authority
beltcollins.com. 3600 SOA NS41.WORLDNIC.com. namehost.WORLDNIC.com. 126021223 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0