adv._domainkey.heyloyalty.com has no MX records.
Question and response
Question
dig adv.domainkey.u2090024.wl025.sendgrid.net. MX
Answer
The response has no answer records.
Authority
wl025.sendgrid.net. 1800 SOA aisha.ns.cloudflare.com. dns.cloudflare.com. 2398213991 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0