mainback.pbxhosting.com.mx has no NS records.
NS records for this zone are defined at pbxhosting.com.mx.
NS records for this zone are defined at pbxhosting.com.mx.
Question and response
Question
dig mainback.pbxhosting.com.mx. NS
Answer
The response has no answer records.
Authority
pbxhosting.com.mx. 86400 SOA dns1.pbxhosting.com.mx. ti.inbtel.com. 2026022105 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0