Setup Postfix as send-only MTA

I have followed the instructions here:
https://netcorecloud.com/tutorials/install-postfix-as-send-only-smtp-server/

However when I try to send the test email I don't receive an email.

Running:
tail /var/log/mail.log
Shows
Dec 31 20:27:46 myHostName postfix/smtp[62043]: connect to in1-smtp.messagingengine.com[66.111.4.75]:25: Connection timed out
Dec 31 20:28:16 myHostName postfix/smtp[62043]: connect to in1-smtp.messagingengine.com[66.111.4.71]:25: Connection timed out
Dec 31 20:28:46 myHostName postfix/smtp[62043]: connect to in1-smtp.messagingengine.com[66.111.4.73]:25: Connection timed out
Dec 31 20:29:16 myHostName postfix/smtp[62043]: connect to in1-smtp.messagingengine.com[66.111.4.72]:25: Connection timed out

I have outgoing connections on port 25 enabled on the cloud firewall.

Not really a mail guru, what am I missing?

I have outgoing connections on port 25 enabled on my cloud firewall.