gmc.claro.com.sv has no CNAME records.
Question and response
Question
dig gmc.claro.com.sv. NS
Answer
The response has no answer records.
Authority
claro.com.sv. 3600 SOA gmc.claro.com.sv. dns.claro.com.sv. 2026011223 10800 3600 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0