Non Payment for service

I am a service provider and provided a service for the Southern Ambitions also trading as Explore SAA. When I sent my invoice I had to wait weeks only to get a part payment. Ever since I am trying to get my money out of them. if they can treat their supplier this way, imagine what they can do to their client. I am posting this as a last resort to get my money out of them. I've tried to call Moses Kamarlie but to no avail. The lady that booked the transport with me Faseega is not taking my calls any longer. when I visited Southern Ambitions office in Rondebosch the vacated the premises. So they knew all along they would not pay me. But their website is still alive. Can I get a response as what to do next? Cyril Williams