This company stole my money

This company stole my money. I have paid R12,190 for a camera they were advertising online. A week later they (a chap named Erson) emailed me saying they did not have the camera in stock and were trying to locate one. Three weeks later I asked for a refund. I have heard nothing from them since. I don't understand why they are selling things they don't possess. I understand if they hadn't updated their website but their refusal to pay back my money is theft and unacceptable.