Unpaid work

I was sent to go sign documents at Durban from Johannesburg. Once we got there they asked me to take a load to Swaziland that very same night and I didn't have passport at that time. I was gone from since Thursday night till the following week Thursday and the promised to pay me since and I have been trying to get the money for a passport but they failed to pay me . Now I seating without a job and I can't afford to do a passport I really don't know what to do.