Apex domains cannot have CNAME records.
Question and response
Question
dig fullsave.info. NS
Answer
fullsave.info. 5 NS b.dns.fullsave.com.
fullsave.info. 5 NS a.dns.fullsave.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0