FnF recovery

Hi ..good to see this type of help online. My question: I left my organization in 2012 Jan as employee and joined same organization after 3months as consultant. Until last month where again I will be joining them as employee. Now they coming up and telling me that your FnF is not settled and I owe them X amount which is for LOP ( leave without pay) of November and December 2011. It Was shocking for me to see this after 3yrs though I'm with company. In 2012 when I left they just send mail in June 2012, To check your FnF settlement follow this PPT steps. Since it was PPT I dint open. And they were never any mail to me or my Hod about recovery amount until last month. So need help for 1. Is it fair or allowed to come after 3yrs when they could not act timely. 2. When checked on LOP details ..1 day was dept off and 2nd was I worked on that day but not marked in records which I missed it. So on telling them to waive it they not agreeing. so the whole to me looks very unfair to employee 1. You come after 3yrs though I'm with you but since I'm consultant you dint check then. 2. In spite of proof for 2days LOP and recommendation from my head Hr not agreeing. 3. My salary for december and coming months not released coz they want to me to pay full amount and I'm fighting for 2days LOP reversal. Kindly suggest what does law state.