Gift settlement cancellation possible ??

Sir, My father has given his property to his brother for running business. His brother has mortgaged the property and got loan of 10 lakhs on 2010. Due to huge loss in the business, he could not able to pay the loan time. Due to huge amount pending with the bank, bank has announced serfasi, came and sealed. My father and brother has approached me and the has given a settlement deed registered without any conditions, to me on 2012. I got loan from other banks and settled and done a mortgage after settlement and paying the EMI for last seven years. My father is having one other property. My father is living with me, my brothers are living in other cities, they got married. Now he lost his all ancestral property and forced me transfer the property. We made a mutual agreement on 100 rs document which is unregistered to interchange the property on 2018 January. which other property is not worth as I spent for last seven years. After that he is not willing to transfer his own property, he is asking the property from me and started threatening me. Now he has made a suit on me that I have given a settlement only for the sake of paying loans, possession has not been handed over, he made a civil suit to cancel the settlement deed. My brother also asks the partition on the property. The whole patta, Tax and EB name has transferred on 2018 July. He made a civil suit on December 2018. Is the cancellation possible in this situation?? How can we proceed the case ? Till not approached any lawyer, my first hearing date on 29th January. Is that 100 rs document will affect whole settlement ? What is the role of my younger brother ? Whether they can ask for the partition? Need your valuable support??