No Service. No response. No tent.

We bought an Oztrail tent from the Oztrail Store. It was defective and the frame failed with the first 2 or 3 times of using it. Unfortunately it failed during a trip to Botswana and we had to struggle to form any kind of shelter with it. After getting home it was returned to the Oztrail Store/Brandhubb. They agreed that the tent was defective and agreed to replace it. Four months later, but no tent. We have now asked for our money back. We have made multiple calls and emails to Darren Adamo at Oztrail and Nicholas Cupido at Brandhubb and have never received a solution, in spite of their promises to attend to the problem. They no longer answer emails or calls. Where to now?? This is sad, because Oztrail is a good brand, but it's product and service have failed us in practice.