Apex domains cannot have CNAME records.
Question and response
Question
dig wl098.sendgrid.net. NS
Answer
wl098.sendgrid.net. 5 NS aisha.ns.cloudflare.com.
wl098.sendgrid.net. 5 NS devin.ns.cloudflare.com.
Authority
The response has no authority records.
Additional
aisha.ns.cloudflare.com. 2 A 108.162.194.186
aisha.ns.cloudflare.com. 2 A 162.159.38.186
aisha.ns.cloudflare.com. 2 A 172.64.34.186
devin.ns.cloudflare.com. 2 A 108.162.195.49
devin.ns.cloudflare.com. 2 A 162.159.44.49
devin.ns.cloudflare.com. 2 A 172.64.35.49
aisha.ns.cloudflare.com. 2 AAAA 2606:4700:50:0:0:0:a29f:26ba
aisha.ns.cloudflare.com. 2 AAAA 2803:f800:50:0:0:0:6ca2:c2ba
aisha.ns.cloudflare.com. 2 AAAA 2a06:98c1:50:0:0:0:ac40:22ba
devin.ns.cloudflare.com. 2 AAAA 2606:4700:58:0:0:0:a29f:2c31
devin.ns.cloudflare.com. 2 AAAA 2803:f800:50:0:0:0:6ca2:c331
devin.ns.cloudflare.com. 2 AAAA 2a06:98c1:50:0:0:0:ac40:2331
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0