Get online support
On this page: https://support.tpg.com.au/email-settings
you have this sentence: IMAP mailboxes can be provided for an annual fee viewable HERE.
The link goes to general support page, not the page specified in the link.
The link is one of the old pages no longer accessible.
Thank you for pointing this out @david64.
We'll raise this with our team as we do not sell any Email account anymore.