ns1.regex.com has no MX records.
Question and response
Question
dig ns1.regex.com. MX
Answer
The response has no answer records.
Authority
regex.com. 86400 SOA ns5.padinet.com. log.log.angin.com. 2022072101 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0