Flat sold by builder illegally and demanding remaining amount

Hello! I had purchased a flat in Indore MP in September 2015 at the price of 19 lakhs, I paid builder 14 lakhs and done with the registration of flat but in the registration document builder wrote 5 lakhs as pdc dated 01/01/2016 which I had to pay him in 3 monthsand now its july and I haven\'t paid the mentioned amount and the reason behind this was that I came to know later that the flat which builder sold to me is illegal and he built a flat in parking area this I came to know from my neighbour, all these things was not informed to my builder as I was not going for any home loan so he didn\'t informed me anything on this, but now I am unable to make the remaining amount of 5lakhs so I was willing to go for mortgage loan but no banker is accepting, my documents, I asked for map and government clearance paper of my flat and he gave me a modified one I am having all that proof as well.Now I am in dilemma of what to do, builder is forcingme to vacate the flat asap or else he will sell the flat to someone in 5lakhs and recover his money and he is saying that he will cancel my sale deed and will present the cheque and in bank and it will bounce and he will cancel the agreement the cheque date is already over as it was given in the month of Jan 2016 its 6 month now.Please guide me what to do in this.