rk5210.way3.com has no MX records.
Question and response
Question
dig rk5210.way3.com. MX
Answer
The response has no answer records.
Authority
way3.com. 3600 SOA ns1.way3.com. dnsadmin.way3.com. 2026022003 3600 1800 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0