Salary hold during probation period

Sir, I was working with a firm in gurgaon and as per employment letter I can take 1.5 leaves per month . This was my first month of probation period and It was very unfortunate that in the first month I took 3 days (un-uniform) medical leaves because I was unwell. And at the very last moment of paying the salary the employer told me your salary is on hold and they will not pay me as I have been terminated . Please suggest what should I do now