Liability of 138 NI Act defaulter

I availed an Agricultural Equipments loan from central cooperative bank in June 2009. Deposited two blank cheques as security and got the handwritten receipt of them showing as blank. Did not pay any penny till March 2015. Bank presented a cheque for 816000/- in March 2015 which was dishonored. I received legal notice. I deposited RS. One Lac in April 2015 and depositing continually and 750000/- deposited till now. Bank made the amount totalling 965000/- upto Dec. 2017. Bank pressurising to clear before 31 Dec. 2017. I need more time. Please guide.