Job harassment.

Dear Sir, My name is Debadyuti Das living in New Delhi for the past 8 yrs. I am working with Market Research Company (The Nielsen India Pvt. Ltd.) and I have been working as freelancer since 8 yrs. I have issued payments via Cheques.Our in-charge has wrongfully misused my credibility regarding my loyalty in work for his personal benefit. Our Manager is also in aligned with him. He had told that after 3 years they will make to work in this organization as payroll. But to my vain they had lied to me and pressurizing me to quit the job without any valid reason. They had issue a yearly bond to work as freelance but I had refused to sign it. They are misusing my efforts for their own personal gain. I had repeatedly asked them for a payroll but they do not reply any. On company norms all the credibility of my work is shown to our to in-charge for his personal gain and promotion. Now I am very confused how I can take necessary action so that they stop this practice immediately and pressurize them so that they take on board for a payroll on this similar company. The details are as follows:- Name- Debadyuti Das. Company name:- The nielsen India Pvt. Ltd. Department:- IMR (Industrial Market Research) Gurgaon.