Company is not paying the pending salary

Hi, i m working in structural consultancy, and i also have same problem of not paid from last 2 month. I have joined company as a senior structural engineer in December 2017, from than i m getting late salary. I have received salary of December in feb 2018.Now when i have asked my employer for may salary, he simply removed me and said that he will not going to pay me a single money. I have an appointment letter and salary slip upto april. Plz help, what should I do.

Last months my sales are low, so management was told me I will not accept you in my company,  so I was resonated for my job in 27/12/2018. The issue is a company not give me my salary and not released me.  So what should I do? 
A company did not give me any note if your business is low, I will not release your salary not mentioned in my official letter or mail.  
Last review meetings company told me we will not tolerate you in my organization so  I was given Resign 27/12/2018,  I was asked in my resign letter if you give me any notice period soi will be served,  but the company did not accept my resign letter and not released me. 
Till the time company not released my salary,  I called my director so he was told me we will not pay your salary because I was paid you extra amount to your company business(Sales), My Director told me I have no fund to give you the salary. 
Please help me what should I do?

Please count me if you have any solution

Thanks
Neeraj Vashishtha