Check Bounce 138

Hello Sir, I purchased Flat in April 2014, and paid all Agreement amount by Check and Home Loan. Stamp Duety & Reg. Amount paid in Cash and Builder has clearly agreed in Sale Agreement that he received it. He has handed over flat and i am staying in it. In Jan 2016, i have filed Consumer Case on Builder for Deficiency in work. In Return Builder Misused check which i guess Amount i have mentioned but Date was blank given during Flat purchase. Now he filed 138 case and saying it is against Stamp Duety & Reg. Amount. For Stamp Duety & Reg. I dont have any receipt and it was paid online from Builders Account. Reg. Amount and deposited Check Amount are not matching for that he is saying few amount paid in cash to my staff and given check for Pending Amount which was bounced. Could you please suggest how i can defend it? Is it possible to prove paid in Cash 2 Year back only when not having any Cash Receipt.? Shall i Defend it or not? What will be the possiblity of Case Result? Or shall i pay the amount and close the matter? What will happen if I will and What will happen if I will not win the case. Please suggest as early as possible. Thanks & Regards