@Dana105 Go to your Reservations and click on the 3 dots on the right hand side of each reservation, drop down list should have GST invoice.
The GST invoice available is for the host fees, guests get there own GST invoice for service fees.
Lots of hosts think airbnb should issue a GST invoice for the full booking amount, unfortunately the rental contract is between the guest and host, you have to send an invoice for the amount you received from the guest
If you are GST registered you send the guest an invoice for the accommodation they paid you for, if not GST registered you cannot issue a GST invoice.