Apex domains cannot have CNAME records.
Question and response
Question
dig towersgross.com. NS
Answer
towersgross.com. 5 NS ns2.towersgross.com.
towersgross.com. 5 NS ns1.towersgross.com.
Authority
The response has no authority records.
Additional
ns1.towersgross.com. 5 A 51.161.41.192
ns2.towersgross.com. 5 A 169.197.143.164
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0