Apex domains cannot have CNAME records.
Question and response
Question
dig telgua.com.gt. NS
Answer
telgua.com.gt. 4 NS ns.telgua.com.gt.
telgua.com.gt. 4 NS ns1.claro.com.gt.
telgua.com.gt. 4 NS ns.comtech.net.gt.
Authority
The response has no authority records.
Additional
ns.telgua.com.gt. 4 A 216.230.128.33
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0