If a passenger asks for a tax invoice, rather than an ordinary invoice, for a fare over $50 (including GST), they must be given one within 28 days of their request.
If the digital platform offers to issue tax invoices on your behalf, you should give them your GST registration details so they can issue tax invoices to your customers for all trips. If they do not, you must provide the passenger with the tax invoice. The tax invoice must contain certain information including your GST registration number.
Any fare under $50 (including GST) does not need a tax invoice, so you can just issue an invoice if a passenger asks for one.