pairserver.com has no MX records.
Question and response
Question
dig pairserver.com. MX
Answer
The response has no answer records.
Authority
pairserver.com. 3600 SOA ns1.pair.com. root.pair.com. 2026022701 3600 300 604800 7200
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0