How can I get the tax invoice with GST amount?

I need the tax invoice with the GST amount (not the invoice pdf in the order page) in order to use a salary sacrifice in Australia. However Apple doesn't provide one? I used to receive them via email but not anymore?

The way I purchase the product this time round is by topping up my Apple account with $$ I have paid for in the past with Apple gift cards. This is through Australia Apple online store.

Is this the reason why Apple doesn't generate a tax invoice with this payment method? If yes, how can I request one?