wl202.sendgrid.net has no MX records.
Question and response
Question
dig wl202.sendgrid.net. MX
Answer
The response has no answer records.
Authority
wl202.sendgrid.net. 1800 SOA aisha.ns.cloudflare.com. dns.cloudflare.com. 2397720418 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0