Thank you for reporting this issue. Our engineering team is aware of this issue and working with Bankwest to resolve the connection. There is a reported product investigation at the moment with INV-73355: Unable to connect with or download transactions from Bankwest, getting error 102.
I'd suggest reaching out to our QuickBooks Online Customer Support Team. By doing so, they'll add your company to the list of affected users. Once added, you'll be notified about the status of the issue via email.