Bad service , do not want to refund , yet they refused me to board

I am disgusted in the manner this airlines operate with Refunds ,My son booked with Quantis airline-through the flight center New Zealand , when he arrived they refused him to board as he did not have a visa to enter Australia, however its states on Google that you can enter Australia as long as you have connecting flight , He had to then may double for a booking through Singapore as he had an appointment in SA with the embassy , Now they not responding to him regarding the refund.