Rent A Student refuses to pay students

Earlier this year decided to seek employment through rent a student. Worked in March and April but till this day have not received payment. When I call to enquire John was rude saying there's nothing he can do I should stop bothering him, he has work to do and i should just wait for month end. Completely different attitude as compared to when I was putting money in their pocket. Debbie has resorted to rejecting my calls and ignoring my smss after she led me to believe I would receive payment by the 11th of August. Searching for them on Twitter also revealed that I am not the 1st student they are doing this to. They have blocked me on their twitter page since I've been openly talking about the treatment I've been getting from them. Taking students for a ride in this economy is truly *********. Pretending to have students interests at heart while making them work for their financial benefit is something i wasn't expecting especially when I used my own money to get to work and gave them a good reputation leading to an extension of the initial working period