postfix.mcxplatform.com.au has no SRV records.
Question and response
Question
dig postfix.mcxplatform.com.au. SRV
Answer
The response has no answer records.
Authority
mcxplatform.com.au. 600 SOA pdns09.domaincontrol.com. dns.jomax.net. 2025041000 28800 7200 604800 600
Additional
. 0 OPT ; payload 1280, xrcode 0, version 0, flags 0