Apex domains cannot have CNAME records.
Question and response
Question
dig realogy.com. NS
Answer
realogy.com. 5 NS ns-724.awsdns-26.net.
realogy.com. 5 NS ns-1765.awsdns-28.co.uk.
realogy.com. 5 NS ns-345.awsdns-43.com.
realogy.com. 5 NS ns-1283.awsdns-32.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0