HL-L3230CDW won't print double sided on W11

I cannot find any way to contact Brother Australia. No phone nos listed, the chat bot can't understand the simplest question, what they call email (I call web mail) gives a 500 - Internal Server error when I submit. Am I correct that only Brother can fix an Internal server error, not a member of the public like myself?

Can anyone assist in contacting their Tech Service, or in installing the recently updated Brother driver that is claimed to work on W11?

At present Microsoft drivers have installed, and (among other things) they don't support 2-sided printing. I have spent ages following various sets of instructions, and trying the various options, unsuccessfully.