FNF Issues - Past Employer's Notice Pay

I joined an NBFC from a Bank in July 2012. The NBFC wanted me to join by July as a result of which I paid Rs 1.08 Lakhs short notice period recovery from my own pocket which was confirmed from the NBFC that they will pay me this amount on joining. Having joined the NBFC, I repeatedly reminded them about the same and after 5 months, they agreed to pay me this Notice recovery amount but paid me only 50% of the same - Rs 50,000. I resigned from the services of this NBFC in February 2013 and just now received the FNF settlement working. To my surprise, they have claimed the Rs 50,000 they paid me as notice buy out to be paid back to them for FNF settlement.
Please advise whether this is correct or not. I believe they cannot claim this amount but would like to know from seniors here.

Hi Mayank,
You may check your appointment order. There could be a similar clause, most probably " If resign from services with in 'x' years, the notice period buyout pay shall be recovered at the time of full and final settlement".
If the deduction is as per appointment order/amendment in appointment order, you just need to follow the clause and here in this case, statutory legislation got no business

Thanks for your reply. I do not recall any such clause in my appointment letter. How can I rebutt the company's claim for the same in the most professional manner? I need to reply to their email which claims this amount to be paid back.
thanks again.