Trademe contacted the person I gave a refund to by accident as I was having a hard time contacting them. The person made contact a few days later and I arranged payment. I had to let them make fortnightly payments as it was my mistake. I have to trust that they will continue payments till they are paid in full. But the main thing is they contacted me and the first payment should be this week. Trademe said to contact them if I didn't hear from the person in a few days.