How to cancel a registered sale deed of land in assam

I had an agreement with Mr. A that if he pay me Rs. 50.0 lakhs than I will return him an amount of Rs. 60.0 lakhs including benefits within 6 months. This amount I have taken for my business purpose. And if I am not able to return the amount then Mr. A can possess my property by giving a value of Rs. 1.5 cr. As the time went there was loss in my business and as a result I couldn't pay Mr. A, Rs. 60.0 as per agreement and commitment. Now he demanded my property by virtue of the deal. As a result I gave him registration of the property. But Mr. A gave me only Rs. 95.0 lakhs including the previous Rs. 50.0 lakhs. remaining Rs. 55.0 lakhs he told me to give after registration of sale deed but till now he has not paid my the remaining Rs. 55.0 lakhs . Moreover the sale deed was executed on 2nd November - 2018. Apart from this I had a mortgage loan from Reliance Home Finance on the said property of land around Rs. 64.0 lakhs. So as he is not paying the amount to me I told him to pay the amount to Reliance Home Finance and give me the know due certificate but he is not paying that amount to Reliance also. Please let me know how to cancel the sale deed.