mxout4.service.a1.net has no CNAME records.
Question and response
Question
dig mxout4.service.a1.net. NS
Answer
The response has no answer records.
Authority
a1.net. 1055 SOA dns1.a1.net. domainadmin.a1.net. 2026022504 10800 3600 1814400 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0