mx01.jschosting.se has no CNAME records.
Question and response
Question
dig mx01.jschosting.se. NS
Answer
The response has no answer records.
Authority
jschosting.se. 3288 SOA dns01.jschosting.se. registry.jsc.nu. 2020032129 21600 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0