Complaint against my company - please suggest me what should i do?

Dear Sir, I have joined xxxxj Finance in Jan 2016 as a Sales Executive in APR Department(Only sale of Apple Iphone) on third party payroll Addeco India. After joining he provide me offer letter gross salary 18k & net inhand 16740. After 1 month my SM say that the Apple company have close his tie up with Bajaj Finance & i have no option for you so i am going to shifted to you in Normal where is your net in hand 8700/-rs only. Now till date 13 Mar 2016 i have not received my salary Jan & Feb & i want to file a case against company that company gave me offer letter 18k salary but after 1 month without any legal notice like mail or hard copy so please suggest me what should i do?

I understand your problem of company not keeping its word and behaving arbitrarily.
During the period you have been working,I am sure you could have made out whether really the agreement for sale of IPhone has really been cancelled.
what I would do is to talk to management about your pay which is not paid for last two months.
Put up your points in writing so that there is documentation about non payment etc.
Are you the only person affected or there are other people also?
Are you in a financial condition to fight a legal battle?
Consult a lawyer for ideas and way ahead.
But before going legal explore talks with your HR and try to get in other affected employees.
You may think in terms of going to local labour officials also.