ns4.raxhosting.com has no MX records.
Question and response
Question
dig ns4.raxhosting.com. MX
Answer
The response has no answer records.
Authority
raxhosting.com. 86400 SOA nsc1.raxhosting.com. support.rax.bg. 2026021701 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0