Apex domains cannot have CNAME records.
Question and response
Question
dig titussteelbuildings.com. NS
Answer
titussteelbuildings.com. 5 NS ns-659.awsdns-18.net.
titussteelbuildings.com. 5 NS ns-1162.awsdns-17.org.
titussteelbuildings.com. 5 NS ns-334.awsdns-41.com.
titussteelbuildings.com. 5 NS ns-672.awsdns-20.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0